Variability in Individual Response to Aerobic Exercise Interventions Among Older Adults

Muscular fitness profiles in relation to the response in body fat during school-based high-intensity intervention

BACKGROUND

We aimed to assess the equivalence of the muscular fitness (MF) between body fat percentage (BFP) responders (RsBFP) and non-responders (NRsBFP) to school-based high-intensity interval training (HIIT). Adolescents aged 16 (N.=73, 42.5% of males) were identified as RsBFP (N.=45) or NRsBFP (N.=28). MF was assessed based on hand strength (HS), abdominal muscle strength (ABS), and leg power (VJ).

METHODS

Profile analysis showed distinct patterns of MF changes in both response categories. Despite the presence of parallelism (Wilks' Λ=0.979, Pillai's V=0.212, P=0.473), a gradient of increasing changes (HS-ABS-VJ) was found in the RsBFP, while a gradient of decreasing changes was shown in the NRsBFP, and a significant level of inequality (F(1,71)=7.823, P=0.047, partial eta-squared [η2p] 0.041).

RESULTS

One-way analysis showed a significant and moderate effect on VJ (F(1,71)=7.080, P=0.010, η2P=0.091), a close to significant effect on ABS (F(1,71)=3.300, P=0.074, η2P=0.044) and lack of an effect on HS (F(1,71)=0.699, P=0.406, η2P=0.010). The test of equal means across the condition categories (separately for RsBFP and NRsBFP) indicated that there was no multivariate statistically significant within-group effect (F(2, 70)=0.517, P=0.599).

CONCLUSIONS

The findings may help teachers assess the potential and indirect changes in muscle performance after employing a body weight intervention (based on the HIIT program). A more targeted approach to treating adolescents with excessive BF, in parallel with improving MF, can be individually tailored.

Semi-supervised exercise training program more effective for individuals with postural orthostatic tachycardia syndrome in randomized controlled trial

PURPOSE

Exercise like any medication requires the correct dose; to be effective the appropriate frequency, duration, and intensity are necessary. This study aimed to assess if a semi-supervised exercise training (ET) program would be more effective at improving aerobic fitness (VO2PEAK), exercise tolerance, and symptoms in individuals with postural orthostatic tachycardia syndrome (POTS) compared to the standard of care (SOC).

METHODS

Subjects were randomized to either the ET or SOC groups (n 26 vs. 23; age 33 ± 11 vs. 37 ± 10 years; VO2PEAK 66 ± 15 vs. 62 ± 15% predicted, ET vs. SOC respectively, p > 0.05). Composite Autonomic Symptom Score (COMPASS 31), 10 min stand test, and cardiopulmonary exercise test were performed at baseline and following 12 weeks. The ET group received an exercise consultation and eight semi-supervised in-person or virtual exercise sessions.

RESULTS

The ET group demonstrated a greater improvement in VO2PEAK, higher or longer tolerance for baseline peak workload, and more often had a delayed symptom onset with exercise than the SOC group (ΔVO2PEAK 3.4 vs. - 0.2 mL/min/kg, p < 0.0001, ΔWorkload 19 ± 17 vs. 0 ± 10 W; Workload time 63 ± 29 vs. 22 ± 30 s; onset-delay 80% vs. 30%, p < 0.05). Individuals in the ET group reported a significant improvement in orthostatic intolerance domain score (p = 0.02), but there was not a significant difference in the improvement in total COMPASS score (- 11.38 vs. - 6.49, p = 0.09).

CONCLUSION

Exercise training was more effective with greater improvements in aerobic fitness, orthostatic symptoms, and exercise tolerance for individuals with POTS when intensity and progression were personalized and delivered with minimal supervision compared to the SOC.

An observational pilot evaluation of the Walk with Ease program for reducing fall risk among older adults

BACKGROUND

Physical activity is an effective method of reducing fall risk among older adults. Previous evaluations of the six-week Walk with Ease (WWE) program have documented benefits to functional outcomes, but the potential effects on reducing fall risk have not been evaluated. This pilot study evaluates outcomes of a community delivered WWE program for potential suitability as a fall risk reduction program.

METHODS

A total of 59 older adults (age > 60) enrolled in a group version of WWE delivered by trained community-based leaders. Complete data (pre- and post-program) from functional fitness tests and behavioral instruments were obtained from 41 participants (aged 74.4 ± 6.6 years, 70% female). Functional outcomes included the 10-foot timed up and go (TUG), 30-second chair stand (CST) and 4-stage balance test (BT) included as part of STEADI, as well as a two-minute step test (ST) and normal gait speed test (GST). Survey assessments included STEADI fall risk screening, self-reported physical activity, and fear of falling measures. Analyses focused on reporting pre-post effect sizes, but paired t-tests were used to test statistical significance of differences.

RESULTS

Improvements in functional performance approached significance for both CST (d = 0.31, p = 0.06) and ST (d = 0.26, p = 0.12), but all other tests were nonsignificant. Survey results demonstrated significant increases in self-reported walking (d = 0.54, p = 0.02) and moderate-to-vigorous physical activity (MVPA; d = 0.56, p = 0.004), but perceived fear of falling and overall fall risk scores had smaller, non-significant, effects (d ranging from 0.01 to 0.31). Stratified analysis suggested that participants screened at an elevated risk for falls at baseline consistently had larger effects on all functional and survey assessments, though the analysis was underpowered to test significance.

CONCLUSIONS

Walk with Ease participation significantly increased self-reported physical activity but did not significantly improve physical function or reduce fall risk. However, consistently larger effect sizes among participants screened as at-risk for falls suggest that the program may be beneficial for those with elevated risk for falls or functional limitations. Further research is needed to document the consistency of these effects among participants with elevated fall risk status.

The Effects of Power Training Frequency on Muscle Power and Functional Performance in Older Women: A Randomized Controlled Trial

ABSTRACT

Katsoulis, K and Amara, CE. The effects of power training frequency on muscle power and functional performance in older women: a randomized controlled trial. J Strength Cond Res 37(11): 2289-2297, 2023-Low-intensity power training (PT) has emerged as an effective method for improving muscle power and functional performance in older adults. However, effects of low training frequencies are less understood and could expand the repertoire of exercise prescription, particularly in older women who experience greater functional disability with age compared with men. This study investigated the impact of frequency of low-intensity (40% of 1 repetition maximum, 1RM) PT on lower-body power and functional performance in healthy older women. Women (74 ± 4 years) were randomized to 12 weeks of PT of 1 (PT1, n = 14), 2 (PT2, n = 17), or 3 (PT3, n = 17) d·wk -1 or wait control (CON, n = 15). Measures included leg press 1RM, knee extension power (KEP), and functional performance (stair climb power, stair climb time, 30-second chair stands, 400-m walk, Short Physical Performance Battery). There were no differences between the frequency of training in changes in leg press 1RM, KEP, or functional performance after 12 weeks. Pre-post data for individual training groups revealed that leg press 1RM improved in all PT groups (20-33%, p < 0.05). Furthermore, KEP improved in PT2 and PT3 by 10 and 12%, respectively, and all PT groups improved in the 30-second chair stands and Short Physical Performance Battery (6-22%), whereas PT1 and PT3 improved in the 400-m walk and PT2 improved in stair climb power and stair climb time after training (4-7%, p < 0.05). One to 3 weekly low-intensity PT sessions can improve functional performance, although improvements in both functional performance and power might require 2 or 3 sessions per week in older healthy women.

Evaluating individual level change in physical function response following an exercise program for cancer survivors

PURPOSE

Cancer survivors physical function response to exercise programs at the group level is well-established. However, to advance toward a more personalized approach in exercise oncology, a greater understanding of individual response is needed. This study utilized data from a well-established cancer-exercise program to evaluate the heterogeneity of physical function response and explore characteristics of participants who did vs. did not achieve a minimal clinically important difference (MCID).

METHODS

Physical function measures (grip strength, 6-min walk test (6MWT), and sit-to-stand) were completed pre/post the 3-month program. Change scores for each participant and the proportion achieving the MCID for each physical function measure were calculated. The independent t-tests, Fisher's exact test, and decision tree analyses were used to explore differences in age, body mass index (BMI), treatment status, exercise session attendance, and baseline value between participants who achieved the MCID vs. those who did not.

RESULTS

Participants (N = 250) were 55 ± 14 years old, majority female (69.2%), white (84.1%), and diagnosed with breast cancer (36.8%). Change in grip strength ranged from - 42.1 to + 47.0 lb, and 14.8% achieved the MCID. Change in 6MWT ranged from - 151 to + 252 m, and 59% achieved the MCID. Change in sit-to-stand ranged from - 13 to + 20 reps, and 63% achieved the MCID. Baseline grip strength, age, BMI, and exercise session attendance were related to achieving MCID.

CONCLUSIONS

Findings illustrate wide variability in the magnitude of cancer survivors' physical function response following an exercise program, and that a variety of factors predict response. Further investigation into the biological, behavioral, physiological, and genetic factors will inform tailoring of exercise interventions and programs to maximize the proportion of cancer survivors who can derive clinically meaningful benefits.

Effect of change of interleukin-6 over time on gait speed response: Results from the lifestyle interventions and independence for elders study

Interleukin (IL)-6 is a well-accepted biomarker of chronic low-grade inflammation possibly conditioning the effect of physical activity (PA) intervention on physical performance in mobility-limited older adults. We evaluated PA intervention effects on 400 m gait speed by yearly change of IL-6 levels in a post-hoc analysis from Lifestyle Interventions and Independence for Elders (LIFE) Study, a multicenter single-blind randomized clinical trial on 1300 sedentary older adults (mean age:78.85 ± 5.23,65.85 % women) at risk for mobility disability. We compared the intervention effects on 400 m gait speed at 12 months follow-up, according to yearly IL-6 change categorized for 1 pg/ml increase or decrease, and subsequently for larger range of yearly variation. Among subjects with yearly IL-6 change between -1 and + 2 pg/ml, we observed a significant difference of gait speed in PA intervention group compared to healthy educational intervention group [0.041 m/s,95 % confidence interval (CI):0.008-0.074,p = 0.006;Cohen's d:0.26, 95 % CI:0.12-0.41). No effects were observed on 400 m gait speed for wider range of variation of plasma IL-6 levels. Limiting change of IL-6 levels under this specific hormetic window could be an important goal to achieve better benefit from PA intervention in terms of gait speed change and prevention of mobility disability.

Interindividual variability of adaptations following either traditional strength or power training combined to endurance training in older men: A secondary analysis of a randomized clinical trial

This study aimed to investigate the interindividual responses following two different concurrent training (CT) regimens in neuromuscular, cardiorespiratory and functional outcomes of older men. Thirty-five older men (65.8 ± 3.9 years) were randomly allocated into one of two CT groups: power training (PT) + high-intensity interval training (HIIT) (n = 17); or traditional strength training (TST) + HIIT (n = 18). Maximal dynamic strength (one-repetition maximum, 1RM), rate of force development at 100 milliseconds (RDF₁₀₀), countermovement jump power (CMJ), quadriceps femoris muscle thickness (QF MT), functional tests (sit-to-stand, timed-up-and-go, and stair climbing), and peak oxygen consumption (VO_2peak) were assessed pre-, post-8 and post-16 weeks of training. The Chi-squared test was used for assessing differences in the prevalence of responders (Rs), non-responders (NRs), and adverse responders (ARs). Similar prevalence of individual responses (Rs, NRs and ARs) between groups were observed after intervention in almost all outcomes: 1RM; power at CMJ; QF MT, and functional tests (P > 0.05). However, a significant difference in the distribution of Rs, NRs and ARs between groups was observed in the RFD₁₀₀ after 16 weeks (p = 0.003), with PT + HIIT group presenting high prevalence of Rs than TST + HIIT (100 % vs. 50 %). The inclusion of explosive-type of contractions in a concurrent training regime induces greater responsiveness in the RFD₁₀₀ in older men, while no differences compared to traditional strength training are observed in maximal strength, muscle size, VO_2peak, and functional performance.

Heart Failure With Preserved Ejection Fraction as an Exercise Deficiency Syndrome: JACC Focus Seminar 2/4

Across differing spectrums of cardiac function and cardiac pathologies, there are strong associations between measures of cardiorespiratory fitness and burden of symptoms, quality of life, and prognosis. In this part 2 of a 4-part series, we contend that there is a strong association among physical activity, cardiorespiratory fitness, and cardiac function. We argue that a chronic lack of exercise is a major risk factor for heart failure with preserved ejection fraction in some patients. In support of this hypothesis, increasing physical activity is associated with greater cardiac mass, greater stroke volumes, greater cardiac output and peak oxygen consumption, and fewer clinical events. Conversely, physical inactivity results in cardiac atrophy, reduced output, reduced chamber size, and decreased ability to augment cardiac performance with exercise. Moreover, physical inactivity is a strong predictor of heart failure risk and death. In sum, exercise deficiency should be considered part of the broad heart failure with preserved ejection fraction phenotype.

Stubborn Exercise Responders-Where to Next?

There is a wide variance in the magnitude of physiological adaptations after resistance or endurance training. The incidence of “non” or “poor” responders to training has been reported to represent as high as 40% of the project’s sample. However, the incidence of poor responders to training can be ameliorated with manipulation of either the training frequency, intensity, type and duration. Additionally, global non-response to cardio-respiratory fitness training is eliminated when evaluating several health measures beyond just the target variables as at least one or more measure improves. More research is required to determine if altering resistance training variables results in a more favourable response in individuals with an initial poor response to resistance training. Moreover, we recommend abandoning the term “poor” responders, as ultimately the magnitude of change in cardiorespiratory fitness in response to endurance training is similar in “poor” and “high” responders if the training frequency is subsequently increased. Therefore, we propose “stubborn” responders as a more appropriate term. Future research should focus on developing viable physiological and lifestyle screening tests that identify likely stubborn responders to conventional exercise training guidelines before the individual engages with training. Exerkines, DNA damage, metabolomic responses in blood, saliva and breath, gene sequence, gene expression and epigenetics are candidate biomarkers that warrant investigation into their relationship with trainability. Crucially, viable biomarker screening tests should show good construct validity to distinguish between different exercise loads, and possess excellent sensitivity and reliability. Furthermore “red flag” tests of likely poor responders to training should be practical to assess in clinical settings and be affordable and non-invasive. Early identification of stubborn responders would enable optimization of training programs from the onset of training to maintain exercise motivation and optimize the impact on training adaptations and health.

Estimating heterogeneity of physical function treatment response to caloric restriction among older adults with obesity

Clinical trials conventionally test aggregate mean differences and assume homogeneous variances across treatment groups. However, significant response heterogeneity may exist. The purpose of this study was to model treatment response variability using gait speed change among older adults participating in caloric restriction (CR) trials. Eight randomized controlled trials (RCTs) with five- or six-month assessments were pooled, including 749 participants randomized to CR and 594 participants randomized to non-CR (NoCR). Statistical models compared means and variances by CR assignment and exercise assignment or select subgroups, testing for treatment differences and interactions for mean changes and standard deviations. Continuous equivalents of dichotomized variables were also fit. Models used a Bayesian framework, and posterior estimates were presented as means and 95% Bayesian credible intervals (BCI). At baseline, participants were 67.7 (SD = 5.4) years, 69.8% female, and 79.2% white, with a BMI of 33.9 (4.4) kg/m². CR participants reduced body mass [CR: -7.7 (5.8) kg vs. NoCR: -0.9 (3.5) kg] and increased gait speed [CR: +0.10 (0.16) m/s vs. NoCR: +0.07 (0.15) m/s] more than NoCR participants. There were no treatment differences in gait speed change standard deviations [CR–NoCR: -0.002 m/s (95% BCI: -0.013, 0.009)]. Significant mean interactions between CR and exercise assignment [0.037 m/s (95% BCI: 0.004, 0.070)], BMI [0.034 m/s (95% BCI: 0.003, 0.066)], and IL-6 [0.041 m/s (95% BCI: 0.009, 0.073)] were observed, while variance interactions were observed between CR and exercise assignment [-0.458 m/s (95% BCI: -0.783, -0.138)], age [-0.557 m/s (95% BCI: -0.900, -0.221)], and gait speed [-0.530 m/s (95% BCI: -1.018, -0.062)] subgroups. Caloric restriction plus exercise yielded the greatest gait speed benefit among older adults with obesity. High BMI and IL-6 subgroups also improved gait speed in response to CR. Results provide a novel statistical framework for identifying treatment heterogeneity in RCTs.

Exercise in Octogenarians: How Much Is Too Little?

The global population is rapidly aging, with predictions of many more people living beyond 85 years. Age-related physiological adaptations predispose to decrements in physical function and functional capacity, the rate of which can be accelerated by chronic disease and prolonged physical inactivity. Decrements in physical function exacerbate the risk of chronic disease, disability, dependency, and frailty with advancing age. Regular exercise positively influences health status, physical function, and disease risk in adults of all ages. Herein, we review the role of structured exercise training in the oldest old on cardiorespiratory fitness and muscular strength and power, attributes critical for physical function, mobility, and independent living. Expected final online publication date for the Annual Review of Medicine, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Response and Adherence of Nursing Home Residents to a Nutrition/Exercise Intervention

OBJECTIVES

Interindividual response variability to nutrition and exercise interventions is extensive in older adults. A group of nursing home (NH) residents participated in a combined intervention. The objective of this post-hoc analysis was to identify factors associated with intervention response measured by change in physical function and body composition.

DESIGN

Post-hoc analyses in the Older Person's Exercise and Nutrition study, a 2-arm randomized trial. The primary outcomes were 30-second Chair Stand Test and composite scores combining physical function and fat-free mass. A secondary outcome was intervention adherence. A 12-week intervention of sit-to-stand exercises and protein-rich nutritional supplements did not improve chair-stand capacity vs control on intention-to-treat basis.

SETTING AND PARTICIPANTS

Residents ≥75 years of age from dementia and somatic units in eight NHs in Sweden.

METHODS

Logistic regressions were performed to define factors associated with response (maintenance/improvement) or nonresponse (deterioration) in 30-second Chair Stand Test, and with intervention adherence. Linear regressions were performed to explore factors associated with response in composite scores.

RESULTS

Mean age of participants (n = 52 intervention, n = 49 control) was 85.8 years. Sarcopenia was occurring in 74%. Sarcopenia at baseline (P = .005) and high adherence to nutritional supplements (P = .002) increased the odds of response. Higher independence in daily activities increased the odds of adherence to sit-to-stand exercises (P = .027) and the combined intervention (P = .020). Allocation to the intervention group and higher self-perceived health were associated with higher composite scores.

CONCLUSIONS AND IMPLICATIONS

NH residents with baseline sarcopenia, better self-perceived health, and high adherence to nutritional supplements benefitted most from a combined nutrition and exercise intervention regarding chair-stand capacity and composite scores of function and fat-free mass. Adherence was related to higher grade of independence. Understanding factors associated with response and adherence to an intervention will help target susceptible residents in most need of support and to optimize the outcome.

Inter-Individual Different Responses to Continuous and Interval Training in Recreational Middle-Aged Women Runners

A crucial subject in sports is identifying the inter-individual variation in response to training, which would allow creating individualized pre-training schedules, improving runner’s performance. We aimed to analyze heterogeneity in individual responses to two half-marathon training programs differing in running volume and intensity in middle-aged recreational women. 20 women (40 ± 7 years, 61 ± 7 kg, 167 ± 6 cm, and VO₂max = 48 ± 6 mL⋅kg^–1⋅min^–1) underwent either moderate-intensity continuous (MICT) or high-intensity interval (HIIT) 12-week training. They were evaluated before and after training with maximal incremental tests in the laboratory (VO₂max) and in the field (time to exhaustion, TTE; short interval series and long run). All the women participated in the same half-marathon and their finishing times were compared with their previous times. Although the improvements in the mean finishing times were not significant, MICT elicited a greater reduction (3 min 50 s, P = 0.298), with more women (70%) improving on their previous times, than HIIT (reduction of 2 min 34 s, P = 0.197, 50% responders). Laboratory tests showed more differences in the HIIT group (P = 0.008), while both groups presented homogeneous significant (P < 0.05) increases in TTE. Both in the short interval series and in the long run, HIIT induced better individual improvements, with a greater percentage of responders compared to MICT (100% vs 50% in the short series and 78% vs 38% in the long run). In conclusion, variability in inter-individual responses was observed after both MICT and HIIT, with some participants showing improvements (responders) while others did not (non-responders) in different performance parameters, reinforcing the idea that individualized training prescription is needed to optimize performance.

A dyadic approach for a remote physical activity intervention in adults with Alzheimer's disease and their caregivers: Rationale and design for an 18-month randomized trial

Adults with Alzheimer's disease and related dementia (ADRD) and their caregivers represent a sizeable and underserved segment of the population with low levels of moderate physical activity (MPA). Options for increasing MPA in community dwelling adults with ADRD and their caregivers are limited. A home-based physical activity intervention delivered remotely via video conferencing to groups of adults with ADRD and their caregivers (RGV), represents a potentially effective approach for increasing MPA in this group. We will conduct an 18-month randomized trial (6 mos. Active intervention, 6 mos. Maintenance, 6 mos. no contact) to compare the effectiveness of the RGV approach with usual care, enhanced with caregiver support (EUC), for increasing MPA in 100 community dwelling adults with ADRD and their caregiver. The primary aim is to compare MPA (min/wk.), assessed by accelerometer, across the 6-mo. active intervention in adults with ADRD randomized to RGV or EUC. Secondarily, we will compare adults with ADRD and their caregivers randomized to RGV or ECU on the following outcomes across 18 mos.: MPA (min/wk.), sedentary time (min/wk.), percentage meeting 150 min/wk. MPA goal, functional fitness, activities of daily living, quality of life, residential transitions, cognitive function, and caregiver burden. Additionally, we will evaluate the influence of age, sex, BMI, attendance (exercise/support sessions), use of recorded sessions, self-monitoring, peer interactions during group sessions, caregiver support, type and quality of dyadic relationship, and number of caregivers on changes in MPA in adults with ADRD and their caregiver across 18 mos.

Spexin as an indicator of beneficial effects of exercise in human obesity and diabetes

Spexin is a novel neuropeptide playing an emerging role in metabolic diseases such as obesity and diabetes via involvement in energy homeostasis and food intake. The present study investigated the effects of obesity and type 2 diabetes (T2D) on circulating levels of spexin and its modulation by physical exercise. Normal-weight (n = 50) and obese adults with and without T2D (n = 69 and n = 66, respectively) were enrolled in the study. A subgroup of obese participants (n = 47) underwent a supervised 3-month exercise programme. Plasma spexin levels were measured by ELISA and correlated with various markers. Plasma spexin levels decreased in obese participants with or without T2D compared with those of normal-weight participants (0.43 ± 0.11, 0.44 ± 0.12 and 0.61 ± 0.23 ng/ml, respectively; P < 0.001). Spexin levels negatively correlated with adiposity markers and blood pressure in the whole study population (P < 0.05). Multiple regression analysis revealed blood pressure was the greatest predictive determinant of plasma spexin levels, which significantly increased in response to physical exercise in obese participants without and with T2D (P < 0.05). Spexin levels significantly increased only in responders to exercise (those with increased oxygen consumption, VO₂ max) with a concomitant improvement in metabolic profile. In conclusion, plasma spexin levels may be an indicator of response to physical exercise.

Interindividual Balance Adaptations in Response to Perturbation Treadmill Training in Persons With Parkinson Disease

BACKGROUND AND PURPOSE

Perturbation training is a promising approach to reduce fall incidence in persons with Parkinson disease (PwPD). This study aimed to evaluate interindividual differences in balance adaptations in response to perturbation treadmill training (PTT) and identify potential outcome predictors.

METHODS

PwPD (n = 43, Hoehn & Yahr stage 1-3.5) were randomly assigned to either 8 weeks of PTT or conventional treadmill training (CTT) without perturbations. At baseline and following intervention, data from 4 domains of balance function (reactive, anticipatory, dynamic postural control, and quiet stance) were collected. Using responder analysis we investigated interindividual differences (responder rates and magnitude of change) and potential predictive factors.

RESULTS

PTT showed a significantly higher responder rate in the Mini Balance Evaluation Systems Test (Mini-BESTest) subscore reactive postural control, compared with CTT (PTT = 44%; CTT = 10%; risk ratio = 4.22, confidence interval = 1.03-17.28). Additionally, while between-groups differences were not significant, the proportion of responders in the measures of dynamic postural control was higher for PTT compared with CTT (PTT: 22%-39%; CTT: 5%-10%). The magnitude of change in responders and nonresponders was similar in both groups. PTT responders showed significantly lower initial balance performance (4/8 measures) and cognitive function (3/8 measures), and were older and at a more advanced disease stage, based on descriptive evaluation.

DISCUSSION AND CONCLUSIONS

Our findings suggest that PTT is beneficial to improve reactive balance in PwPD. Further, PTT appeared to be effective only for a part of PwPD, especially for those with lower balance and cognitive function, which needs further attention.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A1).

Nicotinamide riboside-A missing piece in the puzzle of exercise therapy for older adults?

Maintaining physical mobility is important for preventing age-related comorbidities in older adults. Endurance and resistance training prevent mobility loss in aging, but exercise alone does not always achieve the expected improvements in physical and cardiopulmonary function. Recent preclinical evidence suggests that a reason for the variability in exercise training responses may be the age-related dysregulation of the nicotinamide adenine dinucleotide (NAD+) metabolome. NAD+ is an essential enzymatic cofactor in energetic and signaling pathways. Endogenous NAD+ pool is lower in several chronic and degenerative diseases (e.g., cardiovascular diseases, Alzheimer's and Parkinson's diseases, muscular dystrophies), and also in aging. Exercise requires a higher energy expenditure than a resting state, thus a state of NAD+ insufficiency with reduced energy metabolism, could result in an inadequate exercise response. Recently, the NAD+ precursor nicotinamide riboside (NR), a vitamin B3 derivate, showed an ability to improve NAD+ metabolome homeostasis, restoring energy metabolism and cellular function in various organs in animals. NR has also been tested in older humans and is considered safe, but the effects of NR supplementation alone on physical performance are unclear. The purpose of this review is to examine the preclinical and clinical evidence on the effect of NR supplementation strategies alone and in combination with physical activity on mobility and skeletal muscle and cardiovascular function.

Small samples and increased variability - discussing the need for restricted types of randomization in exercise interventions in old age

Background

Randomization provides an equal chance for participants to be allocated to intervention groups, in order to create an equal distribution of all variables at baseline in all groups. However, this is not guaranteed, particularly if the groups are too small, or if the researched groups consist of older adults. The aims of this commentary are to discuss the increased variability in old age which intensifies the risk of baseline inequalities, to elaborate on the need to estimate potential baseline group differences in small samples of older participants in exercise intervention, to discuss alternative procedures for creating equal groups at baseline and to provide specific guidelines for selecting the design of small studies.

Main body

Small groups with increased inter-individual differences may lead to reduced power, thus differences that truly exist may not be detected, or false group differences may appear in the outcome following the treatment. Studies that focused exclusively on older adults have found increased variability in advanced age. Therefore, baseline group differences are more common in older adults as compared to younger persons, and may lead to misinterpretation of the intervention′s results. Imbalances can be reduced by covariate-adaptive randomization procedures, such as stratified permuted-block randomization or minimization. Specific guidelines are provided for selecting a randomization procedure by assessing the probability of unequal groups at baseline in typical, widely used functional tests in old age. A calculation of the required number of participants for creating equal groups for these functional tests is provided, and can be used when increasing the number of participants is possible. R-scripts specifically created for assessing the probability of unequal groups, or for determining the sample size assuring equal groups, are recommended.

Conclusions

In exercise interventions assessing older adults, it is recommended to have a sample large enough for creating equal groups. If this is not possible, as is the case quite often in intervention studies in old age, it is recommended to assess the probability of inequality in the study groups and to apply an alternative randomization.

Changes of the coronary arteries and cardiac microvasculature with aging: Implications for translational research and clinical practice

Aging results in functional and structural changes in the cardiovascular system, translating into a progressive increase of mechanical vessel stiffness, due to a combination of changes in micro-RNA expression patterns, autophagy, arterial calcification, smooth muscle cell migration and proliferation. The two pivotal mechanisms of aging-related endothelial dysfunction are oxidative stress and inflammation, even in the absence of clinical disease. A comprehensive understanding of the aging process is emerging as a primary concern in literature, as vascular aging has recently become a target for prevention and treatment of cardiovascular disease. Change of life-style, diet, antioxidant regimens, anti-inflammatory treatments, senolytic drugs counteract the pro-aging pathways or target senescent cells modulating their detrimental effects. Such therapies aim to reduce the ineluctable burden of age and contrast aging-associated cardiovascular dysfunction. This narrative review intends to summarize the macrovascular and microvascular changes related with aging, as a better understanding of the pathways leading to arterial aging may contribute to design new mechanism-based therapeutic approaches to attenuate the features of vascular senescence and its clinical impact on the cardiovascular system.

Effects of a Multimodal Exercise Program Plus Neural Gliding on Postural Control, Pain, and Flexibility of Institutionalized Older Adults: A Randomized, Parallel, and Double-Blind Study

BACKGROUND AND PURPOSE

The effect of adding neural mobilization to a multimodal program of exercises has not been investigated, despite its potential positive effects. The aim of this study was to compare the acute effects of a multimodal exercise program and neural gliding against a multimodal exercise program only, on pain intensity, gait speed, Timed Up and Go (TUG) test, lower limb flexibility, and static balance of institutionalized older adults.

METHODS

Older adults who were institutionalized (n = 26) were randomized to receive a multimodal exercise program plus neural gliding or a multimodal exercise program only. Both interventions were delivered twice a week for 8 weeks. Participants were assessed for pain, gait velocity, balance, flexibility, and TUG at baseline and postintervention.

RESULTS

A significant main effect of time for pain intensity (F1,24 = 8.95, P = .006), balance (F1,24 = 10.29, P = .004), and gait velocity (F1,24 = 5.51, P = .028) was observed, indicating a positive impact of both interventions. No other significant effects were found (TUG and flexibility; P > .05).

DISCUSSION

A 45-minute multimodal exercise program, twice a week for 8 weeks, has a positive impact on pain intensity, balance, and gait velocity, but neural gliding has no additional benefit. It is unclear whether dose and type of neural mobilization may have had an impact on results. Considering the structural and physiological changes that tend to occur with age, future studies could explore the effects of neural tensioning or of higher doses of neural mobilization.

CONCLUSIONS

This study suggests that adding neural gliding to a multimodal exercise program has no additional benefit.

Effectiveness of the Pilates method versus aerobic exercises in the treatment of older adults with chronic low back pain: a randomized controlled trial protocol

BACKGROUND

Chronic low back pain is potentially disabling for older adults, and exercise is considered the best treatment. The Pilates method and aerobic exercises have been proven to be effective in pain and function improvement in patients with low back pain, but evidence in the treatment of older adults with low back pain is scarce. Therefore, the objective of this study is to investigate the effectiveness of the Pilates method compared to aerobic exercises in the treatment of older adults with chronic nonspecific low back pain.

METHODS

This is a randomized controlled trial with blinded assessor, to be held in a physical therapy clinic in Sao Paulo, Brazil. Seventy four patients aged 65 to 85 years with chronic nonspecific pain will be randomized into Pilates Group (n = 37) with exercises based on the Pilates method and Aerobic Group (n = 37) with treadmill aerobic exercise. The primary outcomes will be pain intensity and general disability, assessed eight weeks after randomization. The secondary outcomes will be: pain intensity and general disability, assessed six months after randomization; and global perceived improvement, specific disability, dynamic balance, muscle strength (gluteus maximus, gluteus medius, and lateral hip rotators), and pressure pain threshold, assessed eight weeks and six months after randomization. Therapists and patients will not be blinded.

DISCUSSION

This study has the potential to reduce pain and, consequently, improve balance and function of older adults with chronic low back pain with both therapies. However, Pilates may be more effective because the exercises are more targeted to the trunk stabilization muscles. The results of this study may provide valuable information on the effects of Pilates and aerobic exercise in older adults with chronic low back pain and contribute to a better selection of the treatment program according to the patient preference.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02729779 , April 6, 2016.