A higher effort-based paradigm in physical activity and exercise for public health: making the case for a greater emphasis on resistance training

Effect of resistance training volume on body adiposity, metabolic risk, and inflammation in postmenopausal and older females: Systematic review and meta-analysis of randomized controlled trials

PURPOSE

This meta-analytical study aimed to explore the effects of resistance training (RT) volume on body adiposity, metabolic risk, and inflammation in postmenopausal and older females.

METHODS

A systematic search was performed for randomized controlled trials in PubMed, Scopus, Web of Science, and SciELO. Randomized controlled trials with postmenopausal and older females that compared RT effects on body adiposity, metabolic risk, and inflammation with a control group (CG) were included. Independent reviewers selected the studies, extracted the data, and performed the risk of bias and certainty of the evidence (Grading of Recommendations, Assessment, Development, and Evaluation (GRADE)) evaluations. Total body and abdominal adiposity, blood lipids, glucose, and C-reactive protein were included for meta-analysis. A random-effects model, standardized mean difference (Hedges' g), and 95% confidence interval (95%CI) were used for meta-analysis.

RESULTS

Twenty randomized controlled trials (overall risk of bias: some concerns; GRADE: low to very low) with overweight/obese postmenopausal and older females were included. RT groups were divided into low-volume RT (LVRT, ∼44 sets/week) and high-volume RT (HVRT, ∼77 sets/week). Both RT groups presented improved body adiposity, metabolic risk, and inflammation when compared to CG. However, HVRT demonstrated higher effect sizes than LVRT for glucose (HVRT = -1.19; 95%CI: -1.63 to -0.74; LVRT = -0.78; 95%CI:-1.15 to -0.41) and C-reactive protein (HVRT = -1.00; 95%CI: -1.32 to -0.67; LVRT = -0.34; 95%CI, -0.63 to -0.04)) when compared to CG.

CONCLUSION

Compared to CG, HVRT protocols elicit greater improvements in metabolic risk and inflammation outcomes than LVRT in overweight/obese postmenopausal and older females.

Exercise instructors are not consistently implementing the strength component of the UK chief medical officers' physical activity guidelines in their exercise prescription for older adults

Strength training recommendations have been embedded within the UK's Chief Medical Officers' physical activity guidelines since 2011. There is limited evidence that these recommendations are used by exercise instructors in the community to underpin strength training prescription in the older adult population. This study aimed to explore exercise instructors' awareness and utilisation of the guidelines when prescribing strength training to older adults. Fifteen exercise instructors working with older adults in the UK participated in one online interview. A general inductive approach was conducted and thematic analysis allowed for major themes to be identified from the raw data. We found that most exercise instructors (n = 9), but not all (n = 6), were aware of the guidelines. Only one instructor (n = 1) had reportedly implemented the guidelines into their practice; other instructors reported that the guidelines were irrelevant. Instead, each of the instructors had their preferred sources of information that they relied on to underpin their exercise prescription, and each had their own interpretation of 'evidence-based strength training.' This individualised interpretation resulted in exceptionally varied prescription in the community and does not necessarily align with the progressive, evidence-based prescription known to build muscular strength. We suggest that (i) more detail on how to build muscular strength be embedded within the guidelines, (ii) a handbook on how to implement the guidelines be made available, (iii) theoretical and practical teaching materials and courses be updated, and/or (iv) a re-(education) of exercise instructors already in the field may be necessary to bring about a consistent, evidence-based strength prescription necessary for the best possible health and longevity outcomes for our ageing population.

Long-Term Time-Course of Strength Adaptation to Minimal Dose Resistance Training Through Retrospective Longitudinal Growth Modeling

Public health guidelines for resistance training emphasize a minimal effective dose intending for individuals to engage in these behaviors long term. However, few studies have adequately examined the longitudinal time-course of strength adaptations to resistance training. Purpose: The aim of this study was to examine the time-course of strength development from minimal-dose resistance training in a large sample through retrospective training records from a private international exercise company. Methods: Data were available for analysis from 14,690 participants (60% female; aged 48 ± 11 years) having undergone minimal-dose resistance training (1x/week, single sets to momentary failure of six exercises) up to 352 weeks (~6.8 years) in length. Linear-log growth models examined strength development over time allowing random intercepts and slopes by participant. Results: All models demonstrated a robust linear-log relationship with the first derivatives (i.e., changes in strength with time) trending asymptotically such that by ~1-2 years strength had practically reached a "plateau." Sex, bodyweight, and age had minimal interaction effects. However, substantial strength gains were apparent; approximately ~30-50% gains over the first year reaching ~50-60% of baseline 6 years later. Conclusion: It is unclear if the "plateau" can be overcome through alternative approaches, or whether over the long-term strength gains differ. Considering this, our results support public health recommendations for minimal-dose resistance training for strength adaptations in adults.

Assessing affective valence and activation in resistance training with the feeling scale and the felt arousal scale: A systematic review

Evidence suggests affective responses to exercise can influence exercise adherence. However, there is a limited understanding of how and when to measure core affect in resistance training. As such, the objective of this systematic review was to analyze how the Feeling Scale and/or the Felt Arousal Scale have been used in resistance training to assess core affect. Focus was given to the contextual feasibility, timing, and frequency of assessment. A search in PubMed, SPORTDiscus, and PsycINFO databases was conducted (last search date July, 2022) with the purpose of including experimental and non-experimental studies, utilizing the Feeling Scale and/or the Felt Arousal Scale in resistance training, and focused on apparently healthy individuals of any age. Twenty-seven studies (N = 718 participants) published between 2009-2022 were qualitatively analyzed. Both scales appeared to be able to detect core affect within a wide array of intensities, ages, and equipment. As for the timing and frequency of measurement, no apparent standardization was evident. The use of the Feeling Scale, the Felt Arousal Scale, or both, to measure core affect appears to be feasible in resistance training practices. However, a lack of methodological background raises concerns regarding the quality of previous studies' assessments and comparisons of results across studies.

Supporting adolescents' participation in muscle-strengthening physical activity: protocol for the 'Resistance Training for Teens' (RT4T) hybrid type III implementation-effectiveness trial

INTRODUCTION

In Australia, only 22% of male and 8% of female adolescents meet the muscle-strengthening physical activity guidelines, and few school-based interventions support participation in resistance training (RT). After promising findings from our effectiveness trial, we conducted a state-wide dissemination of the 'Resistance Training for Teens' (RT4T) intervention from 2015 to 2020. Despite high estimated reach, we found considerable variability in programme delivery and teachers reported numerous barriers to implementation. Supporting schools when they first adopt evidence-based programmes may strengthen programme fidelity, sustainability, and by extension, programme impact. However, the most effective implementation support model for RT4T is unclear.

OBJECTIVE

To compare the effects of three implementation support models on the reach (primary outcome), dose delivered, fidelity, sustainability, impact and cost of RT4T.

METHODS AND ANALYSIS

We will conduct a hybrid type III implementation-effectiveness trial involving grade 9 and 10 (aged 14-16 years) students from 90 secondary schools in New South Wales (NSW), Australia. Schools will be recruited across one cohort in 2023, stratified by school type, socioeconomic status and location, and randomised in a 1:1:1 ratio to receive one of the following levels of implementation support: (1) 'low' (training and resources), (2) 'moderate' (training and resources+external support) or 'high' (training and resources+external support+equipment). Training includes a teacher workshop related to RT4T programme content (theory and practical sessions) and the related resources. Additional support will be provided by trained project officers from five local health districts. Equipment will consist of a pack of semiportable RT equipment (ie, weighted bars, dumbbells, resistance bands and inverted pull up bar stands) valued at ~$A1000 per school. Study outcomes will be assessed at baseline (T0), 6 months (T1) and 18 months (T2). A range of quantitative (teacher logs, observations and teacher surveys) and qualitative (semistructured interviews with teachers) methods will be used to assess primary (reach) and secondary outcomes (dose delivered, fidelity, sustainability, impact and cost of RT4T). Quantitative analyses will use logistic mixed models for dichotomous outcomes, and ordinal or linear mixed effects regression models for continuous outcomes, with alpha levels set at p<0.025 for the outcomes and cost comparisons of the moderate and high support arms against the low support arm.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the University of Newcastle (H-2021-0418), the NSW Department of Education (SERAP:2022215), Hunter New England Human Research Ethics Committee (2023/ETH00052) and the Catholic Schools Office. The design, conduct and reporting will adhere to the Consolidated Standards of Reporting Trials statement, the Standards for Reporting Implementation Studies statement and the Template for Intervention Description and Replication checklist. Findings will be published in open access peer-reviewed journals, key stakeholders will be provided with a detailed report. We will support ongoing dissemination of RT4T in Australian schools via professional learning for teachers.

TRIAL REGISTRATION NUMBER

ACTRN12622000861752.

Meta-analysis of variation in sport and exercise science: Examples of application within resistance training research

Meta-analysis has become commonplace within sport and exercise science for synthesising and summarising empirical studies. However, most research in the field focuses upon mean effects, particularly the effects of interventions to improve outcomes such as fitness or performance. It is thought that individual responses to interventions vary considerably. Hence, interest has increased in exploring precision or personalised exercise approaches. Not only is the mean often affected by interventions, but variation may also be impacted. Exploration of variation in studies such as randomised controlled trials (RCTs) can yield insight into interindividual heterogeneity in response to interventions and help determine generalisability of effects. Yet, larger samples sizes than those used for typical mean effects are required when probing variation. Thus, in a field with small samples such as sport and exercise science, exploration of variation through a meta-analytic framework is appealing. Despite the value of embracing and exploring variation alongside mean effects in sport and exercise science, it is rarely applied to research synthesis through meta-analysis. We introduce and evaluate different effect size calculations along with models for meta-analysis of variation using relatable examples from resistance training RCTs.

The REtirement in ACTion exercise programme and its effects on elements of long term functionality in older adults

Background

The prevention of mobility-related disability amongst adults is a global healthcare priority. Cost-effective community-based strategies to improve physical function and independence in older adults with mobility limitations are needed. This study investigated the effectiveness of the REtirement in ACTion (REACT) exercise intervention on individual markers of physical function at 6-and 12-months.

Methods

The REACT multicentre randomised controlled trial assigned 777 older adults (female, 514; male 263) (mean age 77·6 [SD 6·8] years) with reduced lower limb physical functioning (Short Physical Performance Battery [SPPB] score 4-9) to receive brief healthy ageing advice or a 12-month, group-based, multimodal exercise programme delivered in local communities. Estimated differences in the three individual component scores of the SPPB (strength, balance, gait speed) and physical functional outcomes recorded at 6- and 12-months were assessed.

Results

The intervention group demonstrated significant improvements in strength (OR = 1.88, 95% CI = 1.36-2.59, p < 0.001) and balance (OR = 1.96, 95% CI = 1.39-2.67, p < 0.001) at 12-months, but not in gait speed (OR = 1.32, 95% CI = 0.91-1.90, p = 0.139). In comparison to the control group, at six-and 12-months, the intervention group reported statistically significant improvements in Mobility Assessment Tool-Short Form (MAT-SF), physical component score from SF-36 questionnaire, and strength and endurance items of subjectively reported physical activity (PASE 10-item). Greater than 75% adherence (attending ≥48 of the 64 exercise sessions delivered in 12-months) was associated with superior functional outcomes.

Conclusion

The REACT exercise programme provides local, regional and national service providers with an effective solution to increase muscle strength and balance in older adults at risk of mobility disability.

Connective Adaptive Resistance Exercise (CARE) Machines for Accentuated Eccentric and Eccentric-Only Exercise: Introduction to an Emerging Concept

Eccentric resistance exercise emphasizes active muscle lengthening against resistance. In the past 15 years, researchers and practitioners have expressed considerable interest in accentuated eccentric (i.e., eccentric overload) and eccentric-only resistance exercise as strategies for enhancing performance and preventing and rehabilitating injuries. However, delivery of eccentric resistance exercise has been challenging because of equipment limitations. Previously, we briefly introduced the concept of connected adaptive resistance exercise (CARE)-the integration of software and hardware to provide a resistance that adjusts in real time and in response to the individual's volitional force within and between repetitions. The aim of the current paper is to expand this discussion and explain the potential for CARE technology to improve the delivery of eccentric resistance exercise in various settings. First, we overview existing resistance exercise equipment and highlight its limitations for delivering eccentric resistance exercise. Second, we describe CARE and explain how it can accomplish accentuated eccentric and eccentric-only resistance exercise in a new way. We supplement this discussion with preliminary data collected with CARE technology in laboratory and non-laboratory environments. Finally, we discuss the potential for CARE technology to deliver eccentric resistance exercise for various purposes, e.g., research studies, rehabilitation programs, and home-based or telehealth interventions. Overall, CARE technology appears to permit completion of eccentric resistance exercise feasibly in both laboratory and non-laboratory environments and thus has implications for researchers and practitioners in the fields of sports medicine, physiotherapy, exercise physiology, and strength and conditioning. Nevertheless, formal investigations into the impact of CARE technology on participation in eccentric resistance exercise and clinical outcomes are still required.

Frequency, intensity and duration of muscle strengthening activity and associations with mental health

OBJECTIVES

Despite growing emphasis on the benefits of physical activity for promoting mental health, inclusion of muscle-strengthening (MS) (e.g., body-weight exercises, resistance machines) activities is limited. Notably, few studies collectively assess MS behavioural frequency, duration, and intensity. To address the gap, the current study examined associations between frequency (days), intensity (rating of perceived exertion in relation to repetitions in reserve [RPE/RIR]), and duration (minutes per typical session) of MS activities on anxiety, depression, and mental well-being.

METHOD

A cross-sectional study of 601 participants (Mean age = 30.92 years [SD = 12.70]; 57.7 % female) across Ireland was conducted. Participants completed a self-report questionnaire containing MS instruments previously used, or adapted from valid and reliable measures (i.e., International Physical Activity Questionnaire IPAQ, RPE/RIR), alongside, the Generalized Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire-8 (PHQ-8) and the Mental Health Continuum- Short Form (MHC-SF). A multivariate regression model was tested in MPLUS, using dummy coding for MS frequency in relation to no activity (i.e., 0-days) non-adherence (i.e., 1-day), adherence (i.e., 2-days) and enhanced adherence (i.e., ≥3 days) to the MS public health guidelines, with the mental health variables representing the dependent variables. Intensity and duration were specified in the model as continuous variables; gender and age were included as statistical controls.

RESULTS

Three or more days engaged in MS activities was associated with fewer anxiety (β = -0.12, p < .05) and depression (β = -0.14, p < .01) symptoms. Increased intensity had a negative association with anxiety (β = -0.10, p < .05) and depression (β = -0.15, p < .001). Unexpectedly, adherence to the MS guidelines (2-days) did not predict any of the mental health outcomes, whereas 1-day of MS activity was associated with fewer depression symptoms (β = -0.11). No effects were observed for mental well-being, and MS duration exerted a null effect across all mental health outcomes.

CONCLUSION

Higher frequency and intensity of MS activities may protect against anxiety and depression symptoms. Doing some MS activities (at least 1-day) is likely more beneficial than none for depression. Evidence-based, MS interventions may help curb mental illness rates, and future longitudinal, intervention-based research could consider inclusion of MS frequency, intensity and duration variables to enhance efforts to identify at-risk groups and trends within physical activity and mental illness surveillance.

Narrative Review of Sex Differences in Muscle Strength, Endurance, Activation, Size, Fiber Type, and Strength Training Participation Rates, Preferences, Motivations, Injuries, and Neuromuscular Adaptations

ABSTRACT

Nuzzo, JL. Narrative review of sex differences in muscle strength, endurance, activation, size, fiber type, and strength training participation rates, preferences, motivations, injuries, and neuromuscular adaptations. J Strength Cond Res 37(2): 494-536, 2023-Biological sex and its relation with exercise participation and sports performance continue to be discussed. Here, the purpose was to inform such discussions by summarizing the literature on sex differences in numerous strength training-related variables and outcomes-muscle strength and endurance, muscle mass and size, muscle fiber type, muscle twitch forces, and voluntary activation; strength training participation rates, motivations, preferences, and practices; and injuries and changes in muscle size and strength with strength training. Male subjects become notably stronger than female subjects around age 15 years. In adults, sex differences in strength are more pronounced in upper-body than lower-body muscles and in concentric than eccentric contractions. Greater male than female strength is not because of higher voluntary activation but to greater muscle mass and type II fiber areas. Men participate in strength training more frequently than women. Men are motivated more by challenge, competition, social recognition, and a desire to increase muscle size and strength. Men also have greater preference for competitive, high-intensity, and upper-body exercise. Women are motivated more by improved attractiveness, muscle "toning," and body mass management. Women have greater preference for supervised and lower-body exercise. Intrasexual competition, mate selection, and the drive for muscularity are likely fundamental causes of exercise behaviors in men and women. Men and women increase muscle size and strength after weeks of strength training, but women experience greater relative strength improvements depending on age and muscle group. Men exhibit higher strength training injury rates. No sex difference exists in strength loss and muscle soreness after muscle-damaging exercise.

The relationship between hypertension and physical activity in middle-aged and older adults controlling for demographic, chronic disease, and mental health variables

To explore the relationship between hypertension and physical activity (PA) in the middle-aged and elderly after controlling demographic characteristics, chronic diseases and mental health variables. The 2018 China Health and Retirement Longitudinal Study (CHARLS) was used to collect the data. A baseline survey of middle-aged and older people was carried out nationally using the PPS sample method to look into their demographic, health state, and other information. The investigation included 4593 adults over 50 with complete data on PA level and hypertension prevalence. Z-test, logistic regression analysis, and linear hierarchical regression analysis were performed on the gathered data using the SPSS 27.0 program. The prevalence of hypertension among middle-aged and senior persons was 12.2%, and the percentage of those who did not have it was 87.8%. Males were more likely than females to have hypertension. Participants who reported high levels of PA made up 49.2% of the total, while those who reported low levels of PA made up 50.8% of the total. High levels of PA were significantly inversely correlated with hypertension (P < .05). There was still a statistically significant relationship between PA and hypertension (P < .05) after controlling demographic factors (gender, age, household registration type, education level, widowhood), chronic disease (arthritis, diabetes, disability, asthma, self-assessment of health, memory disease, stroke, hyperlipidemia) and mental health variables (bad mood and depression). High-level PA is significantly related to the low risk of hypertension. After controlling demographic characteristics, chronic diseases and mental health variables, this correlation is still significant.

Adherence to aerobic and muscle-strengthening components of the physical activity guidelines and mental health

Despite a clear distinction between aerobic and muscle strengthening (MS) components in the physical activity guidelines, public health surveillance has largely focused only on aerobic components, limiting the reach of epidemiological research on the physical activity guidelines. Hence, this study investigated the association between adherence to both components (i.e. aerobic and muscle-strengthening) of the World Health Organization’s physical activity guidelines and mental health among the college student population. A cross-sectional study was conducted among a nationally representative sample of Irish college students (7088 participants, M age: 23.17 years; 50.9% female). Participants were categorized as meeting both components of the guidelines (n = 41%), only the aerobic component (n = 25.3%) or the MS component (n = 7.3%), and neither (n = 26.4%). Group membership effects on mental health was determined through mixed univariate ANOVAs, with a Bonferroni correction for post hoc analyses to assess multiple comparisons. Results revealed that meeting both components of the guidelines was significantly (all p &lt; 0.01) associated with greater self-reported happiness, body image and general health, and less mental ill-being, relative to all other respective groupings. Meeting aerobic or MS components in isolation was significantly (p &lt; 0.05) associated with better happiness, general health and body image compared to not meeting either component. To conclude, 59% of the college-aged population are insufficiently active, and adherence to both guideline components is positively associated with mental health. Co-produced, evidence-based, physical activity interventions are needed in students and could contribute to mental health promotion.

'A Lot of People Just Go for Walks, and Don't Do Anything Else': Older Adults in the UK Are Not Aware of the Strength Component Embedded in the Chief Medical Officers' Physical Activity Guidelines-A Qualitative Study

Strength recommendations have been embedded within the UK's Chief Medical Officers' physical activity guidelines since 2011. In 2019, they were given a more prominent position in the accompanying infographic. However, there is limited evidence that these recommendations have been successful in their population-wide dissemination. This study aimed to explore the engagement of community-dwelling older adults with the guidelines to date and to gain a nuanced understanding of the awareness, knowledge, and action that older adults take to fulfil strength recommendations. A total of fifteen older adults living in the UK participated in one online interview. A general inductive approach was used to generate themes from the data. There were four major themes that were found. 1. The strength component of the physical activity guidelines, 2. Barriers, 3. Motivators, and 4. Solutions. No participants were aware of the strength guidelines. When they were asked what activities they used to fulfil the 'build strength on at least two-days-per-week' criteria, walking, yoga, and Pilates were the most common responses. Ageism and strength training misconceptions were major barriers to participation in strengthening exercise. Older adults were much less aware of the benefits of building strength and strength training participation when compared to aerobic activities, so motivators to participation were generally not specific to strength training. Finally, there are several ways that practitioners can overcome the barriers to strength training participation. Solutions to improving the uptake and adherence to strength training participation are likely to be more successful when they include opportunities for social interaction, ability-appropriate challenge, and provide both short- and long-term benefits.

Set to Fail: Affective Dynamics in a Resistance Training Program Designed to Reach Muscle Concentric Failure

Grounded in hedonic assumptions, evidence suggests that people tend to engage in activities they consider pleasurable and enjoyable, while trying to avoid pain and displeasure. This suggests that the dynamic between positive and negative affect can influence current behavior and the intentions to continue performing. Regarding resistance training (RT), research focusing on how to promote a better affective response is still scarce and much needed. Given existing limitations and theoretical suggestions, a RT program was developed and applied to recreational exercisers in a quasi-experimental design aiming to: (1) explore the affective response dynamic through a continuous assessment after the last set of each exercise; and (2) analyze possible differences of preference and tolerance profiles in affective variables (core affect and enjoyment). For that purpose, 43 participants (21 male and 22 female; M_age = 34.69 ± 6.71 years; M_experience = 8.32 ± 4.54 years; M_BMI = 24.26 ± 2.64 kg/m² ) accepted to participate in this study. Descriptive statistics, correlational, and group comparisons analyses were performed to provide evidence for proposed objectives. The present study showed that measures of affective valence/arousal applied immediately after a set represents a feasible and ecologically valid approach to tap core affect. Results presented evidence that recreationally trained exercisers in a common RT program would need a minimum of one measurement to assess the affective response. However, additional assessments could refine the understanding of exercise pleasurable experience. Results also suggest that exercisers with distinct profiles of preference/tolerance depicted differentiated patterns for the affective response, possibly justifying a distinct approach when promoting affective regulation.

Aerobic or Muscle-Strengthening Physical Activity: Which Is Better for Health?

ABSTRACT

The Physical Activity Guidelines recommend performing 150 min of moderate- to vigorous-intensity aerobic physical activity (MVPA) per week. These guidelines also recommend muscle-strengthening physical activity (MSPA) on ≥2 d·wk-1 for additional benefits including muscular fitness and bone health. The majority of the scientific evidence supporting the PA recommendations for health comes from studies of MVPA while the possible contributions of MSPA in these findings have been overlooked historically. Emerging evidence suggests that MSPA can independently protect against major cardiometabolic risk factors, chronic diseases, and mortality. Additional data from clinical trials indicate that many of the well-known health benefits of exercise, like improvements in cardiovascular disease risk factors, are more robust with combined MVPA and MSPA. This review will clarify the relative benefits of MSPA versus MVPA on health-related outcomes to determine the best type of PA for health.

Who is meeting the strengthening physical activity guidelines by definition: A cross-sectional study of 253 423 English adults?

The current UK physical activity guidelines recommend that adults aged 19 to 65 years perform activity to strengthen muscle and bone a minimum of twice weekly. The number of adults meeting strengthening activity guidelines is lower than for aerobic activity, but estimates vary between studies partly due to differences in how muscle-strengthening activity is defined. We aimed to provide estimates for strengthening activity prevalence in English adults based on a nationally representative sample of n = 253,423 18-65-year-olds. We attempted to quantify the variation in estimates attributable to differences in the way strengthening activity is defined. Finally, we aim to provide a brief descriptive epidemiology of the factors associated with strengthening activity. Adults met guidelines for aerobic activity if they reported the activity equivalent to >150 min/week moderate-intensity exercise. Respondents met strengthening guidelines if they reported at least two bouts per week of strengthening activity. We defined strengthening activity, first, according to criteria used in the Health Survey for England (HSE). Second, we counted bouts of strengthening activities for which we could find evidence of health-related benefits (Evidence). Third, we included bouts of strengthening activity as defined in current UK physical activity guidelines (Guideline). Two-thirds (67%) of adults met guidelines for aerobic activity (69% of men, 65% of women). Less than one-third (29% of men and 24% of women) met guidelines for the HSE definition of strengthening activity. Under the Evidence definition, 16% of men and 9% of women met strengthening guidelines. Using the most-stringent definition (Guideline) just 7.3% of men and 4.1% of women achieved the recommendations for strengthening activity. We found females and older adults (50–65 years) were less likely to meet guidelines for aerobic, strengthening, and combined aerobic plus strengthening activity. The prevalence of meeting activity guidelines was lower in adults from more deprived areas (compared with the least deprived); Adults with lower academic qualifications (Level 1) were less likely to meet activity guidelines than those educated to Level 4 (Degree Level) or higher. Having a limiting disability was associated with a lower prevalence of meeting activity guidelines. Associations between socio-demographic measures and the prevalence of adults meeting activity guidelines were stronger for strengthening activity than for aerobic 51(or combined aerobic plus strengthening) activity Compared with aerobic activity, fewer adults engage in strengthening activity regardless of how it is defined. The range in estimates for how many adults meet strengthening activity guidelines can be explained by variations in the definition of ‘strengthening’ that are used and the specific sports or activities identified as strengthening exercise. When strengthening activity is included, the proportion of English adults meeting current physical activity guidelines could be as high as 1 in 3 but possibly as low as just 1 in 20. A harmonized definition of strengthening activity, that is aligned with physical activity guidelines, is required to provide realistic and comparable prevalence estimates.

A scoping review of interventions to improve strength training participation

Background

Low participation rates (1–31%) and unique barriers to strength training (e.g., specialized knowledge, equipment, perceived complexity) suggest effective strength training interventions may differ from effective aerobic or general physical activity interventions. The purpose of this scoping review was to examine interventions used to improve strength training participation through mapping theory, intervention characteristics, prescription parameters, and behaviour change techniques.

Methods

Recommendations by Levac et al. (2010) and PRISMA-ScR were followed in the conduct and reporting of this review, respectively. Patients and exercise professionals participated in developing the research question and data extraction form, interpreting the findings, and drafting the manuscript. Medline, Embase, PsycINFO, CINAHL, SPORTDiscus, and PubMed databases (inception–December 2020) were searched. The inclusion criteria were (a) original peer-reviewed articles and grey literature, (b) intervention study design, and (c) behavioural interventions targeted towards improving strength training participation. Two reviewers performed data screening, extraction, and coding. The interventions were coded using the Behaviour Change Technique Taxonomy version 1. Data were synthesized using descriptive and frequency reporting.

Results

Twenty-seven unique interventions met the inclusion criteria. Social cognitive theory (n = 9), the transtheoretical model (n = 4), and self-determination theory (n = 2) were the only behaviour change theories used. Almost all the interventions were delivered face-to-face (n = 25), with the majority delivered by an exercise specialist (n = 23) in community or home settings (n = 24), with high variability in exercise prescription parameters. Instructions on how to perform the behaviour, behavioural practice, graded tasks, goal setting, adding objects to the environment (e.g., providing equipment), and using a credible source (e.g., exercise specialist delivery) comprised the most common behaviour change techniques.

Conclusions

Our results highlight gaps in theory, intervention delivery, exercise prescription parameters, and behaviour change techniques for future interventions to examine and improve our understanding of how to most effectively influence strength training participation.

Are Physical Fitness and CRP Related to Framingham Risk Score in HIV+ Adults?

Background. People living with HIV (PLWH) have increased risk of cardiovascular disease (CVD). The Framingham Risk Score (FRS) predicts a 10-year CVD risk. Its relationships to physical fitness and C-reactive protein (CRP) are not well established. The current aim is to determine the links between FRS, physical fitness, and CRP in PLWH. Methods. Participants (n = 87) were assessed on multiple biomarkers. The FRS was calculated with the respective variables. Other variables that correlated significantly with FRS were entered into a regression equation to determine their relationship to FRS. Results. The FRS for men was more than twice that for women (12.8 vs 6.0, P < .001). Men were more fit than women, but most participants were not fit. Aerobic capacity was predictive of FRS in men, but not in women, and muscular strength was not predictive of FRS. Women had more than double the CRP compared with men (7.9 vs 3.5 mg/L, P < .01), and it was unrelated to FRS. Conclusions. In men, aerobic capacity was significantly predictive of FRS, but muscular strength and CRP were unrelated to FRS in both genders. These results do not conclusively demonstrate that physical fitness and CRP are related to FRS in PLWH.

The effects of adding high-intensity of effort resistance training to routine care in persons with type II diabetes: An exploratory randomized parallel-group time-series study

AIMS

This study considered the effects of supervised, low volume, high intensity of effort resistance training compared to continued routine care in persons with type II diabetes.

METHODS

We utilized a randomized parallel-group time-series design. All participants completed baseline testing (T0) and then participated in an educational training intervention regarding the management of their diabetes and were followed up for six months, during which they received routine care before being retested (T1). Participants were then randomly allocated to either continue with routine care (CON) or receive the high intensity of effort resistance training intervention (HIT). Participants from both groups were retested again after six months (T2). All participants were followed up for a further 12 months before being finally tested (T3). Data were available from 57 participants who completed the whole duration of the study (HIT, n = 29; CON, n = 28) for measures of anthropometry (body mass, waist circumference, and BMI), body composition (body fat mass, body fat percentage, lean mass, and visceral fat mass), total body water, phase angle, HbA1c, fasted blood glucose, and subjective wellbeing (WHO-5).

RESULTS

During the initial 6-months of routine care significant improvements were noted for waist circumference, body fat mass, lean mass, body fat percentage, lean mass percentage, visceral fat mass, HbA1c, fasted blood glucose, and subjective wellbeing. During the successive 6-months (intervention) and 18-months (follow-up), data suggest that many of these positive changes during the initial 6-months were negated or reversed for CON. In contrast, participants engaging in HIT continued to show positive changes for waist circumference, body fat mass, lean mass, body fat percentage, lean mass percentage, and visceral fat. For blood markers and wellbeing, HbA1c continued to decrease, fasted blood glucose decreased, and subjective wellbeing continued to increase. These positive responses were still evidenced and significantly different compared to CON after the 12-month follow-up.

CONCLUSION

The results of this exploratory pragmatic trial suggest that the addition of high intensity of effort RT alongside routine care can have a positive impact on a range of outcomes in type 2 diabetics having undergone prior routine care.

Cycle ergometer training and resistance training similarly increase muscle strength in trained men

The aim of this study was to compare two different maximal intensity exercise modality training protocols of similar durations on muscle strength, cardiorespiratory fitness, and lower limb composition in recreationally trained men. Twenty-five trained men (28.9 ± 5.6 years) were randomly divided into Cycle ergometer (4 sets of 30 seconds sprints) and Leg press (4 sets of 10-12 repetitions to momentary failure). Both groups trained three times a week for 5 weeks. Before and after the training period, the participants performed a 10-repetition maximum (10RM) test for knee extension, an incremental exercise test on a treadmill for time to exhaustion (TTE) and peak oxygen consumption (V˙O_2peak) and underwent dual energy X-ray absorptiometry to assess lower limb composition. Knee extension 10RM and TTE increased in both groups with no statistically significant between group (p = 0.614 and p = 0.210). Only cycle ergometer group increased V˙O_2peak (p ₌ 0,012). For all lower limb composition outcomes, changes were minimal. The results suggest that 5 weeks of effort and duration matched exercise protocols using cycle ergometer training or leg press may produce similar strength adaptations.

Effects of Curcumin Supplementation on Inflammatory Markers, Muscle Damage, and Sports Performance during Acute Physical Exercise in Sedentary Individuals

Exhaustive and acute unusual physical exercise leads to muscle damage. Curcumin has been widely studied due to the variety of its biological activities, attributed to its antioxidant and anti-inflammatory properties. Furthermore, it has shown positive effects on physical exercise practitioners. However, there is no literature consensus on the beneficial effects of curcumin in acute physical activities performed by sedentary individuals. Therefore, we systematically reviewed evidence from clinical trials on the main effects of curcumin supplementation on inflammatory markers, sports performance, and muscle damage during acute physical exercises in these individuals. We searched PubMed/MEDLINE, Scopus, Web of Science, and Embase databases, and only original studies were analyzed according to the PRISMA guidelines. The included studies were limited to supplementation of curcumin during acute exercise. A total of 5 studies were selected. Methodological quality assessments were examined using the SYRCLE's risk-of-bias tool. Most studies have shown positive effects of curcumin supplementation in sedentary individuals undergoing acute physical exercise. Overall, participants supplemented with curcumin showed less muscle damage, reduced inflammation, and better muscle performance. The studies showed heterogeneous data and exhibited methodological limitations; therefore, further research is necessary to ensure curcumin supplementation benefits during acute and high-intensity physical exercises. Additionally, mechanistic and highly controlled studies are required to improve the quality of the evidence and to elucidate other possible mechanisms. This study is registered with Prospero number CRD42021262718.

Accuracy in Predicting Repetitions to Task Failure in Resistance Exercise: A Scoping Review and Exploratory Meta-analysis

BACKGROUND

Prescribing repetitions relative to task failure is an emerging approach to resistance training. Under this approach, participants terminate the set based on their prediction of the remaining repetitions left to task failure. While this approach holds promise, an important step in its development is to determine how accurate participants are in their predictions. That is, what is the difference between the predicted and actual number of repetitions remaining to task failure, which ideally should be as small as possible.

OBJECTIVE

The aim of this study was to examine the accuracy in predicting repetitions to task failure in resistance exercises.

DESIGN

Scoping review and exploratory meta-analysis.

SEARCH AND INCLUSION

A systematic literature search was conducted in January 2021 using the PubMed, SPORTDiscus, and Google Scholar databases. Inclusion criteria included studies with healthy participants who predicted the number of repetitions they can complete to task failure in various resistance exercises, before or during an ongoing set, which was performed to task failure. Sixteen publications were eligible for inclusion, of which 13 publications covering 12 studies, with a total of 414 participants, were included in our meta-analysis.

RESULTS

The main multilevel meta-analysis model including all effects sizes (262 across 12 clusters) revealed that participants tended to underpredict the number of repetitions to task failure by 0.95 repetitions (95% confidence interval [CI] 0.17-1.73), but with considerable heterogeneity (Q₍₂₆₁₎ = 3060, p < 0.0001, I² = 97.9%). Meta-regressions showed that prediction accuracy slightly improved when the predictions were made closer to set failure (β =  - 0.025, 95% CI - 0.05 to 0.0014) and when the number of repetitions performed to task failure was lower (≤ 12 repetitions: β = 0.06, 95% CI 0.04-0.09; > 12 repetitions: β = 0.47, 95% CI 0.44-0.49). Set number trivially influenced prediction accuracy with slightly increased accuracy in later sets (β =  - 0.07 repetitions, 95% CI - 0.14 to - 0.005). In contrast, participants' training status did not seem to influence prediction accuracy (β =  - 0.006 repetitions, 95% CI - 0.02 to 0.007) and neither did the implementation of upper or lower body exercises (upper body - lower body =  - 0.58 repetitions; 95% CI - 2.32 to 1.16). Furthermore, there was minimal between-participant variation in predictive accuracy (standard deviation 1.45 repetitions, 95% CI 0.99-2.12).

CONCLUSIONS

Participants were imperfect in their ability to predict proximity to task failure independent of their training background. It remains to be determined whether the observed degree of inaccuracy should be considered acceptable. Despite this, prediction accuracies can be improved if they are provided closer to task failure, when using heavier loads, or in later sets. To reduce the heterogeneity between studies, future studies should include a clear and detailed account of how task failure was explained to participants and how it was confirmed.

Evaluating the reach, effectiveness, adoption, implementation and maintenance of the Resistance Training for Teens program

BACKGROUND

Physical activity guidelines recommend young people engage in regular muscle-strengthening activities (e.g., resistance training [RT]). However, few school-based physical activity interventions have been delivered at-scale or promoted RT. The aim of this study was to evaluate the reach, effectiveness, adoption, implementation and maintenance of the Resistance Training for Teens (RT for Teens) program.

METHODS

Data were collected between August 2015 and October 2020. RE-AIM was operationalized as: (i) Reach: number and characteristics of students estimated to be exposed to the program; (ii) Effectiveness: impact of the program on student-level outcomes measured in a subsample of 750 students from 17 schools; (iii) Adoption: number and representativeness of schools with one or more teachers trained to deliver the program; (iv) Implementation: extent to which the program was delivered as intended; and (v) Maintenance: extent to which the program was sustained in schools.

RESULTS

The estimated program reach was ~ 10,000 students, out of a total student population of ~ 200,000 (~ 5%). Students were from diverse socioeconomic and ethnic backgrounds. Improvements in muscular fitness, RT self-efficacy, perceived cardiorespiratory fitness and flexibility, and participation in muscle-strengthening physical activities were documented. A total of 30 workshops were delivered, involving 468 teachers from 249 schools from diverse geographical regions. Implementation varied considerably, with teachers adapting the program to suit the context of their school and student cohorts. However, RT skill development and the promotion of muscular fitness were the session components delivered most during sessions. Teachers' adherence to the SAAFE (Supportive, Active, Autonomous, Fair and Enjoyable) teaching principles was high. Approximately 30% of teachers (144/476) registered to use the RT for Teens app. At the school-level, 37% (93/249) of schools had at least one registered user (teacher and/or student). A total of 2,336 workouts and 3,116 fitness tests were completed by registered users. Of the 249 schools represented, 51 (20.5%) sent an additional (previously untrained) teacher to a second workshop.

CONCLUSIONS

The RT for Teens program had broad reach and adoption. However, intervention delivery varied considerably across schools and additional support strategies are required to optimize intervention implementation and maintain program delivery over time. Future studies will benefit from the utilization of accepted frameworks, recommendations and guidelines for implementation research.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ACTRN12621000352808), retrospectively registered 1^st February 2021.

Exploring the acute affective responses to resistance training: A comparison of the predetermined and the estimated repetitions to failure approaches

BACKGROUND

In resistance-training (RT), the number of repetitions is traditionally prescribed using a predetermined approach (e.g., three sets of 10 repetitions). An emerging alternative is the estimated repetitions to failure (ERF) approach (e.g., terminating sets two repetitions from failure). Despite the importance of affective responses experienced during RT, a comparison between the two approaches on such outcomes is lacking.

METHODS

Twenty women (age range: 23-45 years) without RT experience completed estimated one repetition maximum (RM) tests in four exercises. In the next two counterbalanced sessions, participants performed the exercises using 70%1RM. Participants completed ten repetitions in all three sets (predetermined condition) or terminated the sets when perceived to be two repetitions away from task-failure (ERF condition). Primary outcomes were affective-valence, enjoyment, and approach-preference and secondary outcomes were repetition-numbers completed in each exercise.

RESULTS

We observed trivial differences in the subjective measures and an approximately even approach-preference split. Under the ERF condition, we observed greater variability in repetition-numbers between participants and across exercises. Specifically, the mean number of repetitions was slightly lower in the chest-press, knee-extension, and lat-pulldown (~1 repetition) but considerably higher in the leg-press (17 vs. 10, p<0.01).

CONCLUSIONS

Both approaches led to comparable affective responses and to an approximately even approach preference. Hence, prior to prescribing either approach, coaches should consider trainee's preferences. Moreover, under the ERF condition participants completed a dissimilar number of repetitions across exercises while presumably reaching a similar proximity to task-failure. This finding suggests that ERF allows for better effort regulation between exercises.

Assessment of muscle-strengthening exercise in public health surveillance for adults: A systematic review

There is strong scientific evidence that muscle-strengthening exercise (i.e. use of weight machines, push-ups, sit-ups) is independently associated with a reduced risk of multiple chronic diseases (e.g. diabetes, hypertension, cardiovascular disease). However, prevalence rates for meeting the muscle-strengthening exercise guideline (≥2 times/week) are significantly lower (~20%) than those reported to meet the aerobic physical activity guideline (e.g. walking, jogging, cycling) (~50%). It is therefore important to understand public health surveillance approaches to assess muscle-strengthening exercise. The aim of this review was to describe muscle-strengthening exercise assessment in public health surveillance. Informed by the PRISMA guidelines, an extensive keyword search was undertaken across 7 electronic data bases. We identified 86,672 possible articles and following screening (n = 1140 in full-text) against specific inclusion criteria (adults aged ≥18 years, English, studies containing <1000 participants), extracted data from 156 manuscripts. Fifty-eight different survey systems were identified across 17 countries. Muscle-strengthening exercise frequency (85.3%), duration (23.7%) and intensity (1.3%) were recorded. Muscle-strengthening exercise questions varied significantly, with some (11.5%) requiring a singular 'yes' vs 'no' response, while others (7.7%) sought specific details (e.g. muscle groups targeted). Assessments of duration and intensity were inconsistent. Very few studies measured the validity (0.6%) and reliability (1.3%) of muscle-strengthening exercise questions. Discrepancy exists within the current assessment systems/surveys used to assess muscle-strengthening exercise in public health surveillance. This is likely to impede efforts to identify at risk groups and trends within physical activity surveillance, and to accurately assess associations between muscle-strengthening exercise and health-related outcomes.

Supporting active ageing before retirement: a systematic review and meta-analysis of workplace physical activity interventions targeting older employees

OBJECTIVE

With the growing representation of older adults in the workforce, the health and fitness of older employees are critical to support active ageing policies. This systematic review aimed to characterise and evaluate the effects on physical activity (PA) and fitness outcomes of workplace PA interventions targeting older employees.

DESIGN

We searched Medline, PreMedline, PsycInfo, CINAHL and the Cochrane Controlled Register of Trials (CENTRAL) for articles published from inception to 17 February 2020. Eligible studies were of any experimental design, included employees aged ≥50 years, had PA as an intervention component and reported PA-related outcomes.

RESULTS

Titles and abstracts of 8168 records were screened, and 18 unique interventions were included (3309 participants). Twelve studies were randomised controlled trials (RCTs). Seven interventions targeted multiple risk factors (n=1640), involving screening for cardiovascular disease risk factors, but had a non-specific description of the PA intervention. Four interventions targeted nutrition and PA (n=1127), and seven (n=235) focused only on PA. Interventions overwhelmingly targeted aerobic PA, compared with only four interventions targeting strength and/or balance (n=106). No studies involved screening for falls/injury risk, and only two interventions targeted employees of low socioeconomic status. Computation of effect sizes (ESs) was only possible in a maximum of three RCTs per outcome. ESs were medium for PA behaviour (ES=0.25 95% CI -0.07 to 0.56), muscle strength (ES=0.27, 95% CI -0.26 to 0.80), cardiorespiratory fitness (ES=0.28, 95% CI -22 to 0.78), flexibility (ES=0.50, 95% CI -0.04 to 1.05) and balance (ES=0.74, 95% CI -0.21 to 1.69). Grading of Recommendations Assessment, Development and Evaluation criteria-rated quality of evidence was 'low' due to high risk of bias, imprecision and inconsistency.

CONCLUSIONS

The lack of high-quality effective workplace PA interventions contrasts the importance and urgency to improve the health and fitness in this population. Future interventions should incorporate strength and balance training and screening of falls/injury risk in multi risk factors approaches.

PROSPERO REGISTRATION NUMBER

CRD42018084863. (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=84863).

Urban Environment and Health: A Cross-Sectional Study of the Influence of Environmental Quality and Physical Activity on Blood Pressure

Few studies have examined the relation between urban built environment and the prevalence of hypertension. This cross-sectional study aimed at assessing the relationship between the environmental quality, physical activity, and stress on hypertension among citizens of Kaunas city, Lithuania. We conducted a survey of 1086 citizens residing in 11 districts to determine their perceptions of environmental quality, health behavior, and health indices. The independent variables included residential traffic flows, access to public transportation and green spaces. Dependent variables included physician-diagnosed hypertension, systolic and diastolic blood pressure, and stress level. We used multivariable logistic regression to assess the associations as odds ratios (OR). The environmental factors beneficially associated with meeting the physical activity recommendations were opportunities for walking to reach the city's green spaces and available relaxation areas. Residents of high noise level districts aged 45-64 years had a significantly higher OR of stress and a higher prevalence of hypertension when age, sex, education status, family status, and smoking were accounted for. However, meeting the physical activity recommendations had a beneficial effect on the risk of hypertension. This study provided evidence that improvement of the district-level built environment supporting citizens' physical activity might reduce the risk of hypertension.

The Impact of Coronavirus (COVID-19) Related Public-Health Measures on Training Behaviours of Individuals Previously Participating in Resistance Training: A Cross-Sectional Survey Study

Introduction

Understanding the impact of lockdown upon resistance training (RT), and how people adapted their RT behaviours, has implications for strategies to maintain engagement in similar positive health behaviours. Further, doing so will provide a baseline for investigation of the long-term effects of these public health measures upon behaviours and perceptions, and facilitate future follow-up study.

Objectives

To determine how the onset of coronavirus (COVID-19), and associated ‘lockdown’, affected RT behaviours, in addition to motivation, perceived effectiveness, enjoyment, and intent to continue, in those who regularly performed RT prior to the pandemic.

Methods

We conducted an observational, cross-sectional study using online surveys in multiple languages (English, Danish, French, German, Italian, Portuguese, Slovakian, Swedish, and Japanese) distributed across social media platforms and through authors’ professional and personal networks. Adults (n = 5389; median age = 31 years [interquartile range (IQR) = 25, 38]), previously engaged in RT prior to lockdown (median prior RT experience = 7 years [IQR = 4, 12]) participated. Outcomes were self-reported RT behaviours including: continuation of RT during lockdown, location of RT, purchase of specific equipment for RT, method of training, full-body or split routine, types of training, repetition ranges, exercise number, set volumes (per exercise and muscle group), weekly frequency of training, perception of effort, whether training was planned/recorded, time of day, and training goals. Secondary outcomes included motivation, perceived effectiveness, enjoyment, and intent to continue RT.

Results

A majority of individuals (82.8%) maintained participation in RT during-lockdown. Marginal probabilities from generalised linear models and generalised estimating equations for RT behaviours were largely similar from pre- to during-lockdown. There was reduced probability of training in privately owned gyms (~ 59% to ~ 7%) and increased probability of training at home (~ 18% to ~ 89%); greater probability of training using a full-body routine (~ 38% to ~ 51%); reduced probability of resistance machines (~ 66% to ~ 13%) and free weight use (~ 96% to ~ 81%), and increased probability of bodyweight training (~ 62% to ~ 82%); reduced probability of moderate repetition ranges (~ 62–82% to ~ 55–66%) and greater probability of higher repetition ranges (~ 27% to ~ 49%); and moderate reduction in the perception of effort experienced during-training (r = 0.31). Further, individuals were slightly less likely to plan or record training during lockdown and many changed their training goals. Additionally, perceived effectiveness, enjoyment, and likelihood of continuing current training were all lower during-lockdown.

Conclusions

Those engaged in RT prior to lockdown these behaviours with only slight adaptations in both location and types of training performed. However, people employed less effort, had lower motivation, and perceived training as less effective and enjoyable, reporting their likelihood of continuing current training was similar or lower than pre-lockdown. These results have implications for strategies to maintain engagement in positive health behaviours such as RT during-restrictive pandemic-related public health measures.

Pre-registration

https://osf.io/qcmpf.

Preprint

The preprint version of this work is available on SportRχiv: https://osf.io/preprints/sportrxiv/b8s7e/.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-021-01438-5.

The Minimum Effective Training Dose Required to Increase 1RM Strength in Resistance-Trained Men: A Systematic Review and Meta-Analysis

BACKGROUND

Increases in muscular strength may increase sports performance, reduce injury risk, are associated with a plethora of health markers, as well as exerting positive psychological effects. Due to their efficiency and effectiveness in increasing total body muscular strength, multi-joint exercises like the powerlifts, i.e.: the squat (SQ), bench-press (BP) and deadlift (DL), are widely used by active individuals as well as athletes in the pursuit of increasing strength. To date, the concept of a minimum dose, i.e. "what is the minimum one needs to do to increase 1-repetition maximum (1RM) strength?" has not been directly examined in the literature, especially in the context of the powerlifts. This review aims to explore the current available evidence around the minimum effective training dose required to increase 1RM strength in trained individuals in an attempt to enhance the practical guidelines around resistance-training as well as provide active individuals, athletes and coaches with more flexibility when designing a training protocol.

METHODS

One reviewer independently conducted the search in a PRISMA systematic approach using PubMed, SportDiscus and Google Scholar databases. The databases were searched with the following search terms/phrases and Boolean operators: "training volume" AND "powerlifting" OR "1RM strength" OR "powerlifters", "low volume" AND "powerlifting" OR "powerlifting" OR "1RM strength", "high vs low volume" AND "powerlifting" OR "1RM strength", "minimum effective training dose 1RM". Meta-analyses were performed to estimate the change in 1RM strength for the lowest dose group in the included studies.

RESULTS

From the initial 2629 studies, 6 studies met our inclusion criteria. All identified studies showed that a single set performed minimum 1 time and maximum 3 times per week was sufficient to induce significant 1RM strength gains. Meta-analysis of 5 studies showed an estimated increase for overall 1RM of 12.09 kg [95% CIs 8.16 kg-16.03 kg], an increase of 17.48 kg [95% CIs 8.51 kg-26.46 kg] for the SQ, and 8.25 kg [95% CIs 0.68 kg-15.83 kg] for the BP. All of the included studies contained details on most of the variables comprising "training dose", such as: weekly and per session sets and repetitions as well as intensity of effort. Specific information regarding load (%1RM) was not provided by all studies.

CONCLUSIONS

The results of the present systematic review suggest that performing a single set of 6-12 repetitions with loads ranging from approximately 70-85% 1RM 2-3 times per week with high intensity of effort (reaching volitional or momentary failure) for 8-12 weeks can produce suboptimal, yet significant increases in SQ and BP 1RM strength in resistance-trained men. However, because of the lack of research, it is less clear as to whether these improvements may also be achievable in DL 1RM strength or in trained women and highly trained strength athletes.

REGISTRATION

This systematic review was registered with PROSPERO (CRD42018108911).

Delivery Approaches Within Exercise Referral Schemes: A Survey of Current Practice in England

BACKGROUND

Exercise referral schemes in England offer referred participants an opportunity to take part in an exercise prescription in a nonclinical environment. The aim of these schemes is to effect clinical health benefits, yet there is limited evidence of schemes' effectiveness, which could be due to the heterogeneity in design, implementation, and evaluation. Additionally, there has been no concerted effort to map program characteristics.

OBJECTIVE

To understand what key delivery approaches are currently used within exercise referral schemes in England.

METHODS

Across England, a total of 30 schemes with a combined total of 85,259 exercise referral scheme participants completed a Consensus on Exercise Reporting Template-guided questionnaire. The questionnaire explored program delivery, nonexercise components, and program management.

RESULTS

Results found that program delivery varied, though many schemes were typically 12 weeks in length, offering participants 2 exercise sessions in a fitness gym or studio per week, using a combination of exercises. Adherence was typically measured through attendance, with nonexercise components and program management varying by scheme.

CONCLUSION

This research provides a snapshot of current delivery approaches and supports the development of a large-scale mapping exercise to review further schemes across the whole of the United Kingdom in order to provide evidence of best practice and delivery approaches nationwide.

Effects of Exercise Combined with Undenatured Type II Collagen on Endurance Capacity, Antioxidant Status, Muscle Lipogenic Genes and E3 Ubiquitin Ligases in Rats

The current study aimed to investigate the effect of exercise combined with undenatured type II collagen (UCII) administration on endurance capacity, lipid metabolism, inflammation, and antioxidant status in rats. Twenty-one male Wistar albino rats were divided into three groups as follows: (1) Sedentary control, (2) Exercise (E), (3) Exercise + UCII (4 mg/kg BW/day; E + UCII). The findings showed that the exhaustive running time in the UCII group was significantly prolonged compared to that of the non-supplemented group (p < 0.001). When compared to the control group, total serum cholesterol (TC, p < 0.05) and triglyceride (TG, p < 0.05) levels decreased, while creatinine kinase (CK) levels increased in the E group (p < 0.001). Serum creatinine kinase levels were reduced in the E + UCII group compared to the E group (p < 0.01). Serum lactate, myoglobin (p < 0.01), and osteocalcin levels (p < 0.01) increased significantly in exercised rats compared to sedentary control rats, while serum lactate (p < 0.01) and myoglobin (p < 0.0001) levels decreased in the E + UCII group compared to control. Additionally, UCII supplementation caused significant increases in antioxidant enzyme activities [SOD (p < 0.01) and GSH-Px (p < 0.05)] and decreases in malondialdehyde (MDA) and tumor necrosis factor (TNF-α) levels (p < 0.001). Muscle lipogenic protein (SREBP-1c, ACLY, LXR, and FAS) levels were lower in the E + UCII group than in other groups. In addition, UCII supplementation decreased muscle MAFbx, MuRF-1, myostatin and increased MyoD levels in exercised rats. Moreover, the E + UCII group had lower muscle inflammatory markers [TNF-α (p < 0.0001) and IL-1β (p < 0.01)] than the control group. These results suggest exercise combined with UCII (4 mg/kg BW/day) modulates lipid, muscle, and antioxidant status in rats.

Twelve weeks of resistance training performed with different number of sets: Effects on maximal strength and resting blood pressure of individuals with hypertension

Objective: This study aimed to verify the effect of resistance training performed with single (SET1) or three sets (SET3) on muscle strength and resting blood pressure (BP) of individuals with hypertension. BP was also assessed during knee extension exercise with submaximal load before and after training. Methods: Thirty-eight patients with hypertension were randomly assigned to a control group (CON: n = 12; 55.6 ± 3.2 years; 65.3 ± 9.3 kg; 163.5 ± 8.6 cm), SET1 group (n = 14; 58.1 ± 2.0 years; 65.4 ± 8.7 kg; 162.4 ± 11.1 cm) or SET3 group (n = 12; 57.9 ± 2.4 years; 66.3 ± 11.4 kg; 161.6 ± 7.5 cm). The training was conducted for 12 weeks (3 d.w^-1; 4 exercises; 12-15 repetitions; moderate intensity). Results: No differences were found in pre-training values for BP and strength between groups. After training, SET3 showed lower values than CON for resting systolic (121.3 ± 8.0 vs 129.3 ± 10.3 mmHg; P = .01) and diastolic BP (73.5 ± 6.0 vs 79.5 ± 7.4 mmHg; P = .02). Muscle strength in bench-press and knee extension exercises increased in SET1 (48.1 ± 6.3 and 71.3 ± 12.2 kg, respectively) and SET3 (50.2 ± 7.8 and 75.2 ± 9.6 kg, respectively) in relation to CON (39.3 ± 5.1 and 62.4 ± 9.9 kg) (P < .01). BP during knee extension (70% of one maximal repetition) did not differ between groups either before or after training. Conclusion: Resistance training with a single set could be interesting when there is a need to increase muscle strength without necessarily reducing resting BP. On the other hand, the performance of three sets increased muscle strength and reduced BP at rest in individuals with hypertension.

Intermittent fasting compromises the performance of eutrophic rats submitted to resistance training

OBJECTIVES

The aim of this study was to analyze the effects of intermittent fasting (IF) on the performance of rats subjected to resistance training ladder climbs (RTLCs).

METHODS

Thirty-two Wistar rats (80-d-old) were placed into one of the following four groups (n = 8/group): control (C), which were fed a standard diet with no exercise; intermittent fasting (IF) rats underwent IF for 16 h/d, fed a standard diet for a period of 8 h/d with no exercise; trained control (TC) were fed a standard diet and submitted to RTLC; and trained intermittent fasting (TIF) underwent IF for 16 h/d, fed a standard diet for a period of 8 h/d, and submitted to RTLC. Training groups completed 6-wk of RTLC (3 × /wk). The maximal load test (MLT) was applied on two occasions: before the first RTLC session and at the end of week 6 of physical training. Its purpose was to compare changes in performance over time. Both blood collection and total extraction of the organs were performed at the end of the experimental period.

RESULTS

Food intake was higher in the TC group than in either the IF or TIF groups. TC supported a higher load (g) during the final MLT compared with the C, IF, and TIF groups, respectively. TC (initial MLT: 371.4 ± 31.1; final MLT: 593.9 ± 33.5) and TIF (initial MLT: 402.3 ± 31.8; final MLT: 495.4 ± 83.3) presented higher values when the pre- and post-RTLC moments were compared. The relative weight of the stomach was higher in TIF than in C and TC rats. There was no difference in aspartate transaminase and alanine transaminase enzyme activities or in creatinine and total cholesterol levels.

CONCLUSIONS

IF negatively affected RTLC performance. IF plus RTLC increased the relative weight of the stomach as well as reduced food intake, without an increase in body weight, suggesting this combination may have promoted dilation of this organ, due, hypothetically, to the scarcity of food for several hours and the energy expenditure generated by physical training.

Skeletal Muscle and Metabolic Health: How Do We Increase Muscle Mass and Function in People with Type 2 Diabetes?

BACKGROUND

Whilst skeletal muscles' primary role is allowing movement, it has important metabolic roles, including in glycemic control. Indeed, evidence indicates that low muscle mass and function are associated with an increased risk of type 2 diabetes, highlighting its importance in the development of metabolic disease.

METHODS

In this mini-review, we detail the evidence highlighting the importance of muscle in type 2 diabetes and the efficacy of resistance exercise in improving glycemic control alongside our approach to increase uptake of such exercise in people with type 2 diabetes. This summary is based in the authors' knowledge of the filed supplemented by a Pubmed search using the terms "muscle," "glycemic control," "HbA1c," "type 2 diabetes," and "resistance exercise."

RESULTS

The main strategy to increases muscle mass is to perform resistance exercise and, although the quality of evidence is low, such exercise appears effective in reducing Glycated Haemoglobin (HbA1c) in people with type 2 diabetes. However, to increase participation we need to improve our understanding of barriers and facilitators to such exercise. Current data indicate that barriers are similar to those reported for aerobic exercise, with additional resistance exercise specific barriers of looking to muscular, increase risk of cardiovascular event, having access to specialized equipment and knowledge of how to use it.

CONCLUSIONS

The development of simple resistance exercises that can be performed anywhere, that use little or no equipment and are effective in reducing HbA1c will be, in our opinion, key to increasing the number of people with type 2 diabetes performing resistance exercise.

Effects of Functional Strength Training on Functional Movement and Balance in Middle-Aged Adults

Functional movement deficiencies cause falls and injuries in adults. Functional strength training (FST) is emerging as a new training method for athletes, middle-aged and older adults, to improve functional movement: The present study was conducted in order to investigate the effects of FST on balance and functional movement in healthy and independent middle-aged adults. The sample for this study consisted of 46 physically active individuals (24 female and 22 male). A total of 46 subjects were divided based on randomly into the functional strength training (FST) group (n = 26) aged: 51.55 ± 3.73 years; height: 168.69 ± 8.8 cm; body mass: 75.88 ± 12.18; and traditional strength training (TST) group (n = 20) age: 52.85 ± 4.01; height: 166.9 ± 9.98; body mass: 76.15 ± 10.45. Each group performed 24 sessions of a training protocol three-time a week. The functional movement was assessed using the functional movement screen (FMS) protocol. Balance performance was determined by using the balance error scoring system (BESS). Bodyweight and body fat ratio were measured using bioelectric impedance. There was a significant statistical difference between FMS total scores after an eight-week FST in the FST group. After the intervention, the functional strength group tended to have significantly better balance control than the traditional strength group (p = 0.01). Statistically, significant differences were observed between pre-test and post-test in the intervention group on BMI, body fat, and body mass (p = 0.01). There were not found significant differences in balance control and FMS score in TST group. As a result of this study, FST positively affected the FMS total score and balance performance in middle-aged adults. Early detections of the deficiencies in functional movement and balance in the middle ages may reduce the risk of insufficiency and fall in adults through targeted functional strength training intervention.

Association between handgrip strength and suicidal ideation in Korean adults

BACKGROUND

It remains unclear whether muscle strength directly links with suicidal thoughts in adults. Given that suicidal ideation is tightly linked to depressive mood, this study sought to investigate the association between handgrip strength and suicidal ideation independent of depressive mood.

METHODS

We performed a cross-sectional analysis of 14,325 adults from the Korean National Health and Nutrition Survey. Handgrip strength was measured by squeezing the handgrip dynamometer using the dominant hand. Suicidal ideation and depressive mood were assessed via the self-reported questionnaires. Logistic regression models were applied to calculate the odds ratio (OR) and 95% confidence interval (CI) for suicidal ideation per 1 kg increase in handgrip strength while adjusting for potential confounders.

RESULTS

The mean age of participants was 49.8 years, 44.7% of whom were male. Suicidal ideation was associated with elderly age, female sex, low socioeconomic status, unhealthy lifestyles, and more comorbid conditions. Depressive mood was similarly associated with each of these factors. Each 1 kg increase in handgrip strength reduced the odds of suicidal ideation in both sexes independent of depressive mood [OR (95% CI), 0.96 (0.94-0.99) for male and 0.97 (0.95-1.00) for female]; in subgroup analysis this association remained robust among elderly men [OR (95% CI), 0.94 (0.91-0.98)].

LIMITATION

Causality and the impact of unmeasured confounders were not addressed.

CONCLUSION

Low handgrip strength is associated with suicidal ideation among adults. Future research is required to confirm our findings and to establish whether strength training can reduce suicidal behaviors, particularly in elderly men.

Effect of high-intensity resistance exercise on cardiometabolic health in older men with osteosarcopenia: the randomised controlled Franconian Osteopenia and Sarcopenia Trial (FrOST)

OBJECTIVES

Sarcopenia is related to the metabolic syndrome (MetS), a cluster of cardiometabolic risk-factors (CRF). Most exercise trials apply aerobic rather than resistance exercise to address CRF, while the strategy for maintaining muscle and bone is the opposite. However, there is considerable evidence that resistance exercise positively affects CRF. In the present study, we determined the effect of high-intensity resistance exercise training (HIT-RT) on CRF represented by the MetS in older men.

METHODS

Forty-three osteosarcopenic and predominately obese older men (>72 years) living independently in Erlangen-Nürnberg, Germany were randomly assigned to two study arms. The HIT-RT group (n=21) conducted a periodised high intensity/effort protocol dedicated to muscle and bone mass and function two times per week, while the control group (CG: n=22) maintained their habitual physical activities. Both groups were supplemented with protein, cholecalciferol and calcium. Study outcomes presented here were the MetS-Z (MetSZ) score and its underlying risk-factors.

RESULTS

After 18 months of intervention, we observed significant effects for the MetSZ score (p<0.001), with significant improvements in the HIT-RT and significant worsening in the CG. In detail, all parameters constituting the MetS contributed to this result, however, only waist-circumference, HDL-cholesterol and mean arterial blood pressure revealed significant effects. No adverse events were reported and high adherence was determined for the HIT-RT-protocol.

CONCLUSION

Continuously supervised HIT-RT is an effective, attractive, feasible and safe method to address cardiometabolic risk factors in community-dwelling men aged 72 years and older. Further, considering the proven effects on musculoskeletal risk factors, the present results indicate a more prominent role for HIT-RT within non-pharmacological prevention strategies of older adults.

TRIAL REGISTRATION NUMBER

NCT03453463.

Multi- and Single-Joint Resistance Exercises Promote Similar Plantar Flexor Activation in Resistance Trained Men

The present study aimed to compare soleus, lateral, and medial gastrocnemius muscles activation during leg press and calf raise exercises in trained men. The study involved 22 trained men (27.1 ± 3.6 years, 82.7 ± 6.6 kg, 177.5 ± 5.2 cm, 3.6 ± 1.4 experience years) who performed one set of each exercise using a 10-repetition maximum (10RM) load in a counterbalanced randomized order and separated by 10 min of rest. The electromyographic signal was measured for the three major plantar flexors: soleus, medial, and lateral gastrocnemius. A comparison between exercises showed that the mean adjusted by peak values during the leg press were 49.20% for the gastrocnemius lateralis, 51.31% for the gastrocnemius medialis, and 50.76% for the soleus. Values for calf raise were 50.70%, 52.19%, and 51.34% for the lateral, medial gastrocnemius, and soleus, respectively. There were no significant differences between exercises for any muscle (lateral gastrocnemius (p = 0.230), medial gastrocnemius (p = 0.668), and soleus (p = 0.535)). The present findings suggest that both leg press and calf raises can be used with the purpose to recruit triceps surae muscles. This bring the suggestion that one can chose between exercises based on personal preferences and practical aspects, without any negative impact on muscle activation.

Mediating effect of health consciousness in the relationship of lifestyle and suboptimal health status: a cross-sectional study involving Chinese urban residents

OBJECTIVE

Suboptimal health status (SHS), a third state between good health and disease, can easily develop into chronic diseases, and can be influenced by lifestyle and health consciousness. No study has surveyed the intermediation of health consciousness on the relationship between lifestyle and SHS. This study aimed to analyse the association of lifestyle and SHS, and intermediation of health consciousness in Chinese urban residents.

DESIGN

A cross-sectional face-to-face survey using a four-stage stratified sampling method.

PARTICIPANTS

We investigated 5803 Chinese urban residents aged 18 years and over. We measured SHS using the Sub-Health Measurement Scale V1.0. We adopted a structural equation model to analyse relationships among lifestyle, health consciousness and SHS. We applied a bootstrapping method to estimate the mediation effect of health consciousness.

RESULTS

Lifestyle had stronger indirect associations with physical (β -0.185, 95% CI -0.228 to -0.149), mental (β -0.224, 95% CI -0.265 to -0.186) and social SHS (β -0.216, 95% CI -0.257 to -0.179) via health consciousness than direct associations of physical (β -0.144, 95% CI -0.209 to -0.081), mental (β -0.146, 95% CI -0.201 to -0.094) and social SHS (β -0.130, 95% CI -0.181 to -0.077). Health consciousness has a strong direct association with physical (β 0.360, 95% CI 0.295 to 0.427), mental (β 0.452, 95% CI 0.392 to 0.510) and social SHS (β 0.434, 95% CI 0.376 to 0.490). Ratio of mediating effect of health consciousness to direct effect of lifestyle with physical, mental and social SHS was 1.28, 1.53 and 1.66, respectively.

CONCLUSIONS

Health consciousness was more important in preventing physical, mental and social SHS than lifestyle. Therefore, it might be useful in changing unhealthy lifestyle and reducing the influence of poor lifestyle on physical, mental and social SHS.

Relationship Between Muscle-Strengthening Activity and Cause-Specific Mortality in a Large US Cohort

INTRODUCTION

Muscle-strengthening activity (MSA) has beneficial effects on hypertension, glucose homeostasis, and other health conditions; however, its association with mortality is not as well understood.

METHODS

We analyzed data from the Cancer Prevention Study-II Nutrition Cohort (data collection 1982-2014), a prospective US cohort that consisted of 72,462 men and women who were free of major chronic diseases; 18,034 of the cohort died during 13 years of follow-up (2001-2014). We used Cox proportional hazards modeling, controlling for various potential confounding factors, to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for MSA (none, >0 to <1 h/wk, 1 to <2 h/wk, and ≥2 h/wk) in relation to mortality risk, independent of and in combination with aerobic physical activity.

RESULTS

The association between MSA and mortality appeared to be nonlinear (quadratic trend P value, <.001). After multivariable adjustment and comparison with no MSA, engaging in less than 2 hours per week of MSA was associated with lowered all-cause mortality (>0 to <1 h/wk: HR = 0.88, 95% CI, 0.82-0.94; 1 to <2 h/wk: HR = 0.90, 95% CI, 0.84-0.97), but engaging in 2 or more hours per week was not associated with reduced risk (HR = 1.01; 95% CI, 0.92-1.09). Associations were similar but not significant for cancer mortality. Engaging in >0 to <1 hr/wk of MSA was associated with a 19% lower risk (HR = 0.81; 95% CI, 0.71-0.92) of cardiovascular disease mortality, but more time spent in MSA was not associated with reduced risk (quadratic trend P value =.005). Associations did not vary by amount of moderate-to-vigorous aerobic physical activity.

CONCLUSION

Engaging in ≥2 hours per week of MSA was associated with lower all-cause mortality, independent of aerobic activity. Reasons for the lack of association with higher amounts of MSA are unclear. Our findings support recommending muscle-strengthening activities for overall health.

Sex Difference in Participation in Muscle-Strengthening Activities

Background

Previous data from the United States Centers for Disease Control and Prevention indicate men are more likely than women to participate in muscle-strengthening activities (e.g., resistance training). However, a recent review by Rhodes et al. concluded there is no reliable sex difference in participation. The purpose of the current paper was to review population-level surveys of participation in muscle-strengthening activities to clarify if a sex difference in participation exists.

Methods

Keyword searches (e.g., "resistance training participation") were performed in PubMed and Google Scholar to identify papers that surveyed a general adult population (N > 1,000) and reported an outcome of the proportion of the population meeting recommendations for "muscle-strengthening activities" (i.e., ≥ 2 times/wk) or participating in resistance training.

Results

Sixteen studies from 6 countries met the inclusion criteria. Irrespective of the measure of participation, population-levels of participation were typically higher in men than women. More men than women met recommendations for muscle-strengthening activities in England (men 34%; women 24%), Finland (men 18.1%; women 16.4%), Northern Ireland (men 25%; women 14%), Scotland (men 30%; women 25%), and the United States (men 34.8%; women 25.8%). For Australia, some studies showed no sex difference in participation, whereas other studies showed greater participation among men.

Conclusion

A sex difference exists in participation in muscle-strengthening activities. Low participation rates in both sexes indicate efforts to encourage participation in men and women are warranted. The results also highlight the need for rigorous definitions of "participation," as the lack of such definitions explains the mixed results reported previously.

Life-Space and Cognitive Decline in Older Adults in Different Social and Economic Contexts: Longitudinal Results from the IMIAS Study

Psychosocial, socioeconomic and sociocultural aspects can influence cognitive function among community-dwelling older adults. Life-space restriction is potentially related to cognitive status. We examined the longitudinal association between life-space mobility and changes in cognitive function in community-dwelling older adults in different social settings of North and South America and Europe. We used data from 1486 participants of the International Mobility in Aging Study (IMIAS) conducted at five sites: Tirana (Albania), Natal (Brazil), Manizales (Colombia), Kingston and Saint-Hyacinthe (Canada). Life-space mobility was assessed using the Life-Space Assessment (LSA) questionnaire at baseline (2012), and the Leganes Cognitive Test was used to evaluate cognitive function at baseline and follow-up (2016). The Quantile regressions (QR) were used to evaluate the factors associated with cognitive score in 2016 by adjusting for the cognitive score in 2012, with two distinct models for analyzing variables. A decrease in the cognitive function was observed at all research sites, except in Manizales. Participants with more restricted life-space at baseline had a decrease in their cognitive function 4 years later (β = -0.79, 95% CI: -1.400 to -0.18, p value<0.01) compared to those with the highest level. This decrease was independent of gender, age, research site, education, income sufficiency, social support, depression, cognitive function at baseline, chronic conditions and physical performance. Restriction in life-space is an important prognostic factor for cognitive function. Maintaining life-space can be a goal in public policies aimed at encouraging healthy aging, and might be useful in clinical practice to promote health status and to monitor older people at higher risk of cognitive decline.

Physical fitness training for stroke patients

BACKGROUND

Levels of physical activity and physical fitness are low after stroke. Interventions to increase physical fitness could reduce mortality and reduce disability through increased function.

OBJECTIVES

The primary objectives of this updated review were to determine whether fitness training after stroke reduces death, death or dependence, and disability. The secondary objectives were to determine the effects of training on adverse events, risk factors, physical fitness, mobility, physical function, health status and quality of life, mood, and cognitive function.

SEARCH METHODS

In July 2018 we searched the Cochrane Stroke Trials Register, CENTRAL, MEDLINE, Embase, CINAHL, SPORTDiscus, PsycINFO, and four additional databases. We also searched ongoing trials registers and conference proceedings, screened reference lists, and contacted experts in the field.

SELECTION CRITERIA

Randomised trials comparing either cardiorespiratory training or resistance training, or both (mixed training), with usual care, no intervention, or a non-exercise intervention in stroke survivors.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed quality and risk of bias, and extracted data. We analysed data using random-effects meta-analyses and assessed the quality of the evidence using the GRADE approach. Diverse outcome measures limited the intended analyses.

MAIN RESULTS

We included 75 studies, involving 3017 mostly ambulatory participants, which comprised cardiorespiratory (32 studies, 1631 participants), resistance (20 studies, 779 participants), and mixed training interventions (23 studies, 1207 participants). Death was not influenced by any intervention; risk differences were all 0.00 (low-certainty evidence). There were few deaths overall (19/3017 at end of intervention and 19/1469 at end of follow-up). None of the studies assessed death or dependence as a composite outcome. Disability scores were improved at end of intervention by cardiorespiratory training (standardised mean difference (SMD) 0.52, 95% CI 0.19 to 0.84; 8 studies, 462 participants; P = 0.002; moderate-certainty evidence) and mixed training (SMD 0.23, 95% CI 0.03 to 0.42; 9 studies, 604 participants; P = 0.02; low-certainty evidence). There were too few data to assess the effects of resistance training on disability. Secondary outcomes showed multiple benefits for physical fitness (VO2 peak and strength), mobility (walking speed) and physical function (balance). These physical effects tended to be intervention-specific with the evidence mostly low or moderate certainty. Risk factor data were limited or showed no effects apart from cardiorespiratory fitness (VO2 peak), which increased after cardiorespiratory training (mean difference (MD) 3.40 mL/kg/min, 95% CI 2.98 to 3.83; 9 studies, 438 participants; moderate-certainty evidence). There was no evidence of any serious adverse events. Lack of data prevents conclusions about effects of training on mood, quality of life, and cognition. Lack of data also meant benefits at follow-up (i.e. after training had stopped) were unclear but some mobility benefits did persist. Risk of bias varied across studies but imbalanced amounts of exposure in control and intervention groups was a common issue affecting many comparisons.

AUTHORS' CONCLUSIONS

Few deaths overall suggest exercise is a safe intervention but means we cannot determine whether exercise reduces mortality or the chance of death or dependency. Cardiorespiratory training and, to a lesser extent mixed training, reduce disability during or after usual stroke care; this could be mediated by improved mobility and balance. There is sufficient evidence to incorporate cardiorespiratory and mixed training, involving walking, within post-stroke rehabilitation programmes to improve fitness, balance and the speed and capacity of walking. The magnitude of VO2 peak increase after cardiorespiratory training has been suggested to reduce risk of stroke hospitalisation by ˜7%. Cognitive function is under-investigated despite being a key outcome of interest for patients. Further well-designed randomised trials are needed to determine the optimal exercise prescription, the range of benefits and any long-term benefits.

Efficacy of School-Based Interventions for Improving Muscular Fitness Outcomes in Adolescent Boys: A Systematic Review and Meta-analysis

BACKGROUND

It has been reported that boys' and girls' physical activity (PA) levels decline throughout adolescence. Boys are at risk of physical inactivity during adolescence; however, in intervention research, they are an under-represented group relative to girls. It is suggested that the school environment may be central to developing interventions that support adolescents in meeting the current PA guidelines. The aim of this systematic review and meta-analysis was to investigate the efficacy of school-based physical activity interventions for improving muscular fitness (MF) in adolescent males.

METHODS

This systematic review and meta-analysis followed the preferred reporting systems for meta-analyses guidelines and was registered on PROSPERO (Registration number: CRD42018091023). Eligible studies were published in English within peer-reviewed articles. Searches were conducted in three databases, with an additional grey literature search in Google Scholar. Studies investigating MF outcomes were included.

RESULTS

There were 43 data sets identified across 11 studies, from seven countries. Overall methodological quality of the studies was moderate-to-strong. Interventions targeting MF evidenced a small-to-medium effect (g = 0.32, CI 0.17, 0.48, p < 0.00). Subgroup analyses of MF delivery method resulted in small-to-medium effects: upper limb MF measures (g = 0.28, 95% CI - 0.02, 0.58, p = 0.07), lower limb MF measures (g = 0.28, 95% CI 0.09, 0.68, p = 0.03), combined MF activities (g = 0.24, 95% CI - 0.04 to 0.49, p = 0.05), plyometric activities (g = 0.39, 95% CI 0.09, 0.68, p = 0.01), body weight (g = 0.27, 95% CI - 0.10, 0.65, p = 0.15), and traditional MF methods (g = 0.43, 95% CI 0.09, 0.78, p = 0.01).

CONCLUSIONS

School-based interventions which aimed to increase MF outcomes in adolescent boys demonstrated small-to-moderate effects. Traditional and plyometric methods of resistance training appear to be the most effective form of PA delivery in adolescent males. More quality research is required to assess the impact of MF delivered in the school environment to inform future intervention design.

Exercise effects on brain and behavior in healthy mice, Alzheimer's disease and Parkinson's disease model-A systematic review and meta-analysis

This systematic review and meta-analysis examines how exercise modifies brain and behavior in healthy mice, dementia (D) and Parkinson disease (PD) models. A search was performed on the Medline and Scopus electronic databases (2008-2019). Search terms were "mice", "brain", "treadmill", "exercise", "physical exercise". In the total, 430 were found but only 103 were included. Animals n = 1,172; exercised 4-8 weeks (Range 24 h to 32 weeks), 60 min/day (Range 8-120 min per day), and 10/12 m/min (Range 0.2 m/min to 36 m/min). Hippocampus, cerebral cortex, striatum and whole brain were more frequently investigated. Exercise improved learning and memory. Meta-analysis showed that exercise increased: cerebral BDNF in health (n = 150; z = 5.8, CI 3.43-12.05; p < 0.001 I2 = 94.3 %), D (n = 124; z = 4.18, CI = 2.22-9.12; p < 0.001; I2 = 93.7 %) and PD (n = 16 z = 4.26, CI 5.03-48.73 p < 0.001 I2 = 94.8 %). TrkB improved in health (n = 84 z = 5.49, CI 3.8-17.73 p < 0.001, I2 = 0.000) and PD (n = 22; z = 3.1, CI = 2.58-67.3, p < 0.002 I2 = 93.8 %). Neurogenesis increased in health (n = 68; z = 7.08, CI 5.65-21.25 p < 0.001; I2 17.58) and D model (n = 116; z = 4.18, CI 2.22-9.12 p < 0.001 I2 93.7 %). Exercise augmented amyloid clearance (n = 166; z = 7.51 CI = 4.86-14.85, p < 0.001 I2 = 58.72) and reduced amyloid plaques in D models (n = 49; z = 4.65, CI = 3.94-15.3 p < 0.001 I2 = 0.000). In conclusion, exercise improved brain and behavior, neurogenesis in healthy and dementia models, reduced toxicity and cerebral amyloid. Evidence regarding inflammation, oxidative stress and energy metabolism were scarce. Studies examining acute vs chronic exercise, extreme training and the durability of exercise benefit were rare. Vascular or glucose metabolism changes were seldom reported.

Effects of three low-volume, high-intensity exercise conditions on affective valence

A common barrier to exercise is "lack of time". Accordingly, interest in low-volume, high-intensity training has grown exponentially since this activity is considered time-efficient. However, the high-intensity nature of this exercise may frequently result in feelings of displeasure creating another barrier for many people. The purpose of this study was to compare affective (pleasure-displeasure) responses to three low-volume, high-intensity exercise conditions, including a novel shortened-sprint protocol. Using a within-subjects, randomised crossover experiment, healthy participants (N = 36) undertook a single bout of: 1) traditional reduced-exertion, high-intensity interval training (TREHIT), 2) a novel, shortened-sprint REHIT (SSREHIT) protocol, and 3) sprint continuous training (SCT). Affect and perceived efforts were recorded throughout exercise using the Feeling Scale (FS) and the 15-point Borg Rating of Perceived Exertion (RPE) scale, respectively. Enjoyment was recorded 5 min post-exercise using the Exercise Enjoyment Scale (EES). Differences were found for FS (condition by time interaction: P = 0.01_GG, η² = 0.26), RPE (P = 0.01_GG, η² = 0.23), and enjoyment (P < 0.01) with all outcomes favouring SSREHIT. Shortened-sprint protocols may diminish feelings of displeasure and might be a time-efficient yet tolerable exercise choice to help motivate some people to increase their physical activity and fitness.