Attention to the principles of exercise training in exercise studies on prostate cancer survivors: a systematic review

Case studies on psychosocial factors that help make exercise programmes for prostate cancer patients self-sustaining

OBJECTIVES

Patients with prostate cancer (PCa) benefit from regular exercise, but it is difficult for patients to maintain an exercise regime. We examined two exercise programmes that have proven to be self-sustaining with the goal of identifying features they share that may contribute to their success.

METHODS

We compared the FC Prostata football (soccer) league in Denmark and the 'Butts in a Boat' (BIAB) dragon-boating team in Canada. The FC Prostata Project Coordinator and the BIAB team leaders provided information on their programmes' history and structure.

RESULTS

Both programmes are team-based with regularly scheduled intense exercise at their core. In both cases, social activities evolved spontaneously, starting with the men going out for food and/or drinks after practices. The sustainability of these programmes may be driven by the regular socialisation linked to the fitness activities.

CONCLUSIONS

Our case studies suggest that exercise programmes for PCa patients may have a good chance of being self-sustaining, if they are: (1) centred around intense exercise, (2) of a team nature, (3) structured to promote egalitarianism and avoid one-on-one competition within teams, yet (4) have some competitions between teams. The data suggest that informal social activities organised by patients after team practices may be important for building fellowship and strengthening patients' commitment to exercise both for themselves and for their team members.

A comparison of aerobic- and resistance-emphasised exercise on cardiometabolic health and quality of life in men receiving androgen deprivation therapy for prostate cancer: Protocol for a feasibility trial

BACKGROUND

Those with intermediate and high-risk prostate cancer typically receive androgen deprivation therapy (ADT) as part of their treatment. ADT often results in extensive side effects including increased risk of cardiometabolic disease. Many ADT side effects can be influenced by exercise, both resistance and aerobic training. Exercise regimes typically combine aerobic and resistance exercise but the appropriate emphasis for achieving the broadest range of therapeutic benefits has yet to be determined. We propose to determine the feasibility of undertaking a larger trial comparing a resistance- vs an aerobic-emphasised exercise intervention in men with prostate cancer undergoing ADT. The trial will also investigate preliminary evidence of difference between arms for cardiometabolic health and quality of life outcomes.

METHODS

This is a 6-month randomised two-armed feasibility trial. Prostate cancer patients undergoing ADT and radiotherapy will be recruited (n = 24) and randomised to either a resistance- or aerobic-emphasised group. Participants will attend twice-weekly supervised individual or small group sessions, with 75% of exercise time in the primary exercise modality. The primary outcome will be feasibility, determined via assessment of recruitment, retention, adherence, safety, and acceptability. Secondary outcomes will include quality of life, body composition, vascular indices, aerobic and muscular fitness and cardiometabolic health blood biomarkers.

CONCLUSION

It is envisaged that the trial will provide valuable information and preliminary difference data that will aid in the design of an efficacious larger trial that will adopt a major and minor emphasis approach to the scheduling of resistance and aerobic exercise.

Safety, Feasibility, and Acceptability of a Multisite Individualized Exercise Intervention for People with Multiple Myeloma

INTRODUCTION

High rates of disease- and treatment-related symptoms, such as bone lesions, in people with multiple myeloma (MM) create uncertainty on the safety and feasibility of exercise. This study determined the safety, feasibility, and acceptability of an individualized exercise medicine program for people with MM at any disease stage.

METHODS

A multisite, randomized waitlist-controlled trial was conducted of an individualized, high-intensity aerobic, resistance, and impact-loading exercise program. The exercise sessions were supervised twice weekly by accredited exercise physiologists, with one additional unsupervised session per week, for 12 wk. Safety was determined by number of adverse and serious adverse events. Feasibility outcome measures were study eligibility, recruitment, adherence, and attrition. Acceptability was determined by qualitative interviews and subjective levels of enjoyment.

RESULTS

Of 203 people with MM screened, 88% were eligible, with 34% accepting participation (60 people) and 20% attrition for the between-group analysis, meeting a priori criteria (≥25% and <25%, respectively). No adverse or serious adverse events attributed to testing and/or exercise training were reported. Attendance at supervised exercise sessions was 98%, with 45% completion of the home-based exercise sessions. Adherence rates were 35%, 63%, and 34% for the aerobic, resistance, and impact-loading protocols, with 55%, 80%, and 37% of participants meeting a priori criteria (75% of protocol). Acceptability of the exercise program was high (mean, 82%; 95% confidence interval, 78%-87%) and highly supported by qualitative responses.

CONCLUSIONS

An individualized, high-intensity aerobic, resistance, and impact-loading exercise medicine program is safe and acceptable, and feasible by some measures for people with MM. Adherence to the prescribed exercise protocols was limited by comorbidities and disease symptoms. Strategies to improve unsupervised exercise completion are warranted in this population.

Designing effective exercise intervention trials for prostate cancer cohorts: a qualitative study on experiences and views of exercise oncology researchers

BACKGROUND

Exercise intervention research has shown promising results in preventing and reversing the side effects caused by prostate cancer and its' treatment. However, there are still unanswered questions and the need for additional research. As the field of exercise oncology in the context of prostate cancer presents unique challenges and complexities, seeking the advice of experienced exercise oncology researchers before initiating a similar trial could help to design more effective and efficient studies and help avoid pitfalls.

METHODS

A qualitative descriptive study design and a nonprobability, purposive sampling method was employed. An interview guide was developed and included topics such as recruitment, retention, programme goals, research design, health considerations, treatment considerations, adverse events, exercise prescription and outcome tools. Individual semi-structured interviews were conducted and interviews were transcribed and analysed using thematic analysis.

RESULTS

Eight individuals with extensive experience working with prostate cancer patients in exercise oncology research settings were interviewed. Four main themes and seven subthemes were generated and supported by the data. Theme 1 highlighted the critical role of recruitment, with associated subthemes on recruitment barriers and recruitment methods. Theme 2 explored the positives and negatives of home-based programmes. Theme 3 focused on specific health characteristics, exercise prescription and outcome measure factors that must be considered when working with prostate cancer cohorts. Finally, theme 4 centered around the emotional dimensions present in exercise oncology trials, relating to both researchers and study participants.

CONCLUSION

Exercise oncology remains a challenging area in which to conduct research. Learning from experienced personnel in the field offers valuable information and guidance that could impact the success of future trials.

Safety and feasibility of exercise interventions in patients with hematological cancer undergoing chemotherapy: a systematic review

OBJECTIVE

Exercise during and after cancer treatment has established quality of life and health benefits. However, particularly for patients with hematological cancer clear recommendations regarding the safety and feasibility of exercise are under-investigated. The aim of our systematic review was to summarize the literature regarding the feasibility and safety of exercise interventions in patients diagnosed with hematological cancer undergoing chemotherapy.

METHOD

A systematic literature review was conducted using PubMed, SPORTDiscus, MEDLINE, Science Direct, and Web of Science electronic databases. Eligible studies were scientific publications reporting the feasibility and/or safety of an exercise intervention program carried out in inpatient patients diagnosed with hematological cancer undergoing chemotherapy.

RESULT

Out of 12 studies (six RCTs) included in this review, six investigations reported results with regard to safety and 10 with regard to feasibility. While all studies claim that their exercise interventions were safe and/or feasible, it is noteworthy that this claim often remains unsupported as detailed information on how the feasibility of the intervention was asserted is missing.

CONCLUSION

Exercise appears to be safe and feasible in hematological cancer patients. However, due to a striking lack of information on how the feasibility of the intervention was asserted, contextualizing the results and deducing recommendations for further studies remains challenging. Further research should therefore incorporate information on the execution of the exercise intervention in more detail.

Effects of exercise mode and intensity on patient-reported outcomes in cancer survivors: a four-arm intervention trial

PURPOSE

The aim of this study was to compare the effects of different exercise modes (aerobic, resistance) and intensity prescriptions (standard, polarized, undulating) on patient-reported outcomes (PROs) in cancer survivors.

METHODS

107 breast or prostate cancer survivors (52% females, age 58 ± 10 years, 6-52 weeks after primary therapy) performed one out of four training programs, two sessions/week, over 12 weeks: work rate-matched vigorous intensity aerobic training (AT_Standard, n = 28) and polarized intensity aerobic training (AT_Polarized, n = 26) as well as volume-matched moderate intensity resistance training (RT_Standard, n = 26) and daily undulating intensity resistance training (RT_Undulating, n = 27). Health-related quality of life (HRQoL, EORTC-QLQ-C30) and cancer-related fatigue (CRF, MFI-20) were assessed at baseline, at the end of intervention and after a 12-week follow-up without further prescribed exercise.

RESULTS

Over the intervention period, HRQoL-function-scales of the EORTC-QLQ-C30 improved over time (p = .007), but no group*time interaction was observed (p = .185). Similarly, CRF values of the MFI-20 improved over time (p = .006), but no group*time interaction was observed (p = .663). When including the follow-up period and pooling the AT and the RT groups, HRQoL-function-scales developed differently between groups (p = .022) with further improvements in RT and a decline in AT. For CRF no significant interaction was found, but univariate analyses showed a non-significant trend of more sustainable effects in RT.

CONCLUSIONS

AT and RT with different work rate-/volume-matched intensity prescriptions elicits positive effects on HRQoL and CRF, without one regimen being significantly superior to another over the intervention period. However, RT might result in more sustainable effects compared to AT over a follow-up period without any further exercise prescription.

CLINICAL TRIAL REGISTRATION

The study was registered at clinicaltrials.gov (NCT02883699).

Reporting Attendance and Resistance Exercise Compliance in Men with Localized Prostate Cancer

PURPOSE

Resistance exercise is a well-established intervention to counteract musculoskeletal and metabolic toxicities from prostate cancer treatment. In this study, we reported resistance exercise attendance and compliance, and examined if these variables can influence changes in outcomes of interest in men with localized or locally advanced prostate cancer.

METHODS

A total of 83 prostate cancer patients (age, 68.2 ± 7.0 yr; body mass index, 27.7 ± 3.8 kg·m -2 ) who had undergone 6 months of resistance-based exercise and had data available on exercise training from logbook records were examined. Attendance outcomes such as missed sessions, interruptions and permanent discontinuation, and metrics such as dosage completed (sessions × number of exercises × sets × repetitions × external load), compliance, tolerance, reductions, and escalations were assessed. Outcomes assessed were body composition, physical function, and muscle strength.

RESULTS

Median resistance exercise attendance was 80.6%, with a median resistance exercise compliance of 88.5% (interquartile range [IQR], 61.1%-107.1%) per participant. A median of 11 (IQR, 1-26) and 0 (IQR, 0-2) sessions were escalated or reduced, respectively. Significant improvements were observed in whole-body lean mass, 400-m walk, repeated chair rise, leg press, and chest press strength after 6 months of intervention ( P < 0.05) regardless of resistance exercise compliance ( Ptrend = 0.199-0.950). Participants with higher levels of resistance exercise compliance presented greater improvements in trunk fat mass ( Ptrend = 0.026) and appendicular lean mass ( Ptrend = 0.047).

CONCLUSIONS

A higher resistance exercise compliance led to greater improvements in regional fat and lean mass, whereas physical function and muscle strength improvements were achieved with lower compliance. In addition, patients experienced a high number of dose escalations during the intervention. These findings are important to improve the reproducibility/precision of exercise medicine prescription.

A systematic review of exercise studies for individuals hospitalized with an acute exacerbation of chronic obstructive pulmonary disease: Focus on the principles of exercise training

BACKGROUND

For exercise interventions to be effectively reproduced or applied in a "real world" clinical setting, clinical trials must thoroughly document all components of the exercise prescription and ensure that participants adhere to each component. However, previous reviews have not critically examined the quality of exercise prescription of inpatient Pulmonary Rehabilitation (PR) programs.

OBJECTIVE

The objectives of this review were to evaluate the (a) application of the principles of exercise training, (b) reporting of the frequency, intensity, time and type (FITT) components of exercise prescription, and (c) reporting of patient's adherence to the FITT components in intervention studies for patients admitted to hospital for an acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

METHODS

Relevant scientific databases were searched for randomized controlled trials (RCTs) that compared in-hospital PR with usual care for people hospitalized with AECOPD. Title and abstract followed by full-text screening were conducted independently by two reviewers. Data were extracted and synthesized to evaluate the application of the principles of exercise training and the reporting/adherence of the FITT components.

RESULTS

Twenty-seven RCTs were included. Only two applied all principles of exercise training. Specificity was applied by 70%, progression by 48%, overload by 37%, initial values by 89% and diminishing returns and reversibility by 37% of trials. Ten trials adequately reported all FITT components. Frequency and type were the components most reported (85% and 81%, respectively), while intensity was less frequently reported (52%). Only three trials reported on the patient's adherence to all four components.

CONCLUSIONS

Studies have not adequately reported the exercise prescription in accordance with the principles of exercise training nor reported all the FITT components of the exercise prescription and patient's adherence to them. Therefore, interpretation of the current literature is limited and information for developing exercise prescriptions to individuals hospitalized with an AECOPD is lacking.

Patterns and determinants of adherence to resistance and endurance training during cancer treatment in the Phys-Can RCT

Background

Knowledge regarding adherence is necessary to improve the specificity of exercise interventions during cancer treatment. We aimed to determine adherence to resistance and endurance training interventions in parallel; identify subgroups with similar adherence characteristics; and examine determinants of these subgroups.

Methods

In the Phys-Can randomised controlled trial, participants (n = 577, 81% women, mean(SD) age 59(12) years, and 50% with BMI ≥ 25 kg/m²) starting (neo-) adjuvant treatment for breast, colorectal or prostate cancer were randomized to 6-month of high (HI) or low-to-moderate intensity (LMI) supervised, group-based resistance training and individual home-based endurance training, with or without behavior change support. Adherence was calculated as performed exercise volume as a proportion of prescribed exercise volume (0–100%), overall (HI and LMI groups) and for frequency, intensity, type and time (FITT principles) (HI group). Adherence to resistance training was plotted against adherence to endurance training overall and for each FITT principle. K-means cluster analysis was used to identify subgroups with similar adherence characteristics. Potential determinants of subgroup membership were examined using multinomial logistic regression.

Results

We found a positive curvilinear correlation between adherence to resistance and endurance training overall. A similar correlation was seen for adherence to frequency of resistance vs. endurance training in the HI group. In the HI group, adherence to resistance training intensity and time was > 80% for almost all participants. For endurance training adherence ranged from 0 to 100% for each of the FITT principles. Three clusters were identified, representing low, mixed, and high adherence to resistance and endurance training overall. Participants with higher age (Relative risk ratio [95% CI]; LMI: 0.86[0.77–0.96], HI: 0.83[0.74–0.93]), no behaviour change support (LMI: 0.11[0.02–0.56], HI: 0.20[0.05–0.85]), higher cardiorespiratory fitness (LMI: 0.81[0.69–0.94], HI: 0.80[0.69–0.92]), more fatigue (according to the reduced activity subscale of the MFI questionnaire) (LMI: 0.48[0.31–0.73], HI: 0.69[0.52–0.93]) or higher quality of life (LMI: 0.95[0.90–1.00], HI: 0.93[0.88–0.98]) were less likely to be in the low than the high adherence cluster whether randomised to LMI or HI training. Other determinants were specific to those randomised to LMI or HI training.

Conclusions

In an exercise intervention during cancer treatment, adherence to resistance and endurance training were positively correlated. Personalisation of interventions and additional support for some subgroups of participants may improve adherence.

Trial registrationNCT02473003 (clinicaltrials.gov, Registered 16/06/2015).

A Brief Overview of the Effects of Exercise and Red Beets on the Immune System in Patients with Prostate Cancer

Research over the past few decades has focused on the use of functional ingredients such as an active lifestyle and proper diet as a treatment for many diseases in the world. Recent studies have shown a variety of health benefits for red beets and their active ingredients such as antioxidant, anti-inflammatory, anti-cancer, blood pressure and fat reduction, anti-diabetic, and anti-obesity effects. This review article examines the effects of exercise and red beet consumption and the effective mechanisms of these two interventions on cellular and molecular pathways in prostate cancer. However, there is a significant relationship between an active lifestyle and proper diet with the incidence of cancer, and the use of these natural interventions for cancer patients in the treatment protocol of avoidance patients. Furthermore, this review article attempts to examine the role and effect of exercise and beetroot nutrition on prostate cancer and provide evidence of the appropriate effects of using natural interventions to prevent, reduce, and even treat cancer in stages. In addition, we examine the molecular mechanisms of the effectiveness of exercise and beetroot consumption. Finally, the use of natural interventions such as exercising and eating beets due to their antioxidant, anti-inflammatory, and anti-cancer properties, due to the lack or low level of side effects, can be considered an important intervention for the prevention and treatment of cancer.

Attention to Progression Principles and Variables of Exercise Prescription in Workplace-Related Resistance Training Interventions: A Systematic Review of Controlled Trials

Background

The workplace is an important setting for adult health promotion including exercise training such as resistance training (RT). Since the reporting of exercise training interventions is generally inconsistent, the objective of this systematic review was to investigate the attention to principles of RT progression and variables of RT exercise prescription in workplace-related RT interventions.

Methods

A systematic literature search was conducted in the databases LIVIVO, PubMed, SPORTDiscus, and Web of Science (2000–2020). Controlled trials with apparently healthy “employees” and a main focus on RT were included. RT principles and variables were extracted and rated by two reviewers (reported, not reported, or unclear). Sum scores for each RT intervention and percentages regarding each principle and variable were calculated.

Results

Overall, 21 articles were included (18 primary studies, 3 protocols). Summarized narratively, the interventions showed different positive effects on strength- or performance-related and/or health- or complaint-related outcomes. The reporting of the RT principles and variables was varied [progressive overload: 94% of the studies, specificity: 78%, variation (periodization): 39%, muscle action: 94%, loading: 94%, volume; 67%, exercise selection: 89%, exercise order: 47%, rest periods between sets: 33%, rest periods between exercises: 27%, repetition velocity: 44%, and frequency: 100%].

Conclusion

Several key RT principles and variables were reported inconsistently, reducing reproducibility and pointing to the need for standardized RT intervention reporting in workplace-related interventions. Exercise science and workplace promotion should be further linked, since accurate reporting is a prerequisite for transferring robust findings into practice.

Feasibility and Safety of Physical Exercise to Preserve Bone Health in Men With Prostate Cancer Receiving Androgen Deprivation Therapy: A Systematic Review

OBJECTIVE

Men with prostate cancer (PCa) receiving androgen deprivation therapy (ADT) experience the loss of bone mineral density (BMD) and lean body mass, which can increase their risk of falls and fractures. Physical exercise programs with appropriate components and dosage are suggested to preserve BMD and muscle strength, thereby potentially reducing accidental falls and fractures and associated morbidity and mortality. These benefits can be obtained if exercise programs are feasible and safe and if patient adherence is adequate. This systematic review investigates the feasibility and safety of exercise programs aimed at preventing the risk of accidental falls and fractures and BMD loss in men with PCa undergoing ADT.

METHODS

MEDLINE, Embase, CINAHL, and the Cochrane Library were searched from database inception to June 7, 2021. Randomized controlled trials were included when they analyzed the feasibility and safety of experimental exercise programs targeting bone health in men with PCa receiving ADT. Two reviewers independently selected the studies, assessed their methodological quality, and extracted the data. Exercise feasibility was measured through recruitment, retention, and adherence rates. Exercise safety was measured through the number, type, and severity of adverse events. Furthermore, the components, setting, intensity, frequency, and duration of exercise programs were extracted.

RESULTS

Ten studies were included, with a total of 633 participants. Exercise consisted of a combination of aerobic, resistance, and impact-loading exercise or football training. Exercise is feasible in men with PCa undergoing ADT, although football training should be prescribed with caution for safety reasons.

CONCLUSION

Multicomponent exercise programs targeting bone health seem feasible and safe in this population; however, adverse events should be systematically documented according to current guidelines.

IMPACT

The study shows that men with PCa receiving ADT can safely perform exercise programs to preserve bone health and supports that those programs should become part of lifestyle habits.

LAY SUMMARY

Men with PCa who are receiving ADT can safely perform exercise programs to preserve bone health and should make exercise an important part of their lifestyle.

Do Patients with Prostate Cancer Benefit from Exercise Interventions? A Systematic Review and Meta-Analysis

Men diagnosed and treated for prostate cancer experience severe adverse effects on quality of life (QoL) and metabolic health, some of which may be preventable or reversible with exercise, the benefits of which healthcare providers and patients increasingly acknowledge, though existing evidence on its effects varies in significance and magnitude. We aimed to review the effect of exercise on QoL and metabolic health in a broad prostate cancer population. A systematic search was conducted in nine databases and eligible trials were included in the meta-analytic procedure. All outcomes were stratified into aerobic exercise, resistance exercise, and a combination of both. The review identified 33 randomised controlled trials (2567 participants) eligible for inclusion. Exercise had a borderline small positive effect on cancer-specific QoL (standardised mean difference (SMD) = 0.10, 95% confidence interval (CI) -0.01-0.22), and a moderate to large effect on cardiovascular fitness (SMD = 0.46, 95% CI 0.34-0.59) with aerobic exercise being the superior modality (SMD = 0.60, 95% CI 0.29-0.90). A positive significant effect was seen in lower body strength, whole-body fat mass, general mental health, and blood pressure. No significant effect was seen in fatigue, lean body mass, and general physical health. We thereby conclude that exercise is effective in improving metabolic health in men diagnosed with prostate cancer, with aerobic exercise as the superior modality. The effect of exercise on QoL was small and not mediated by choice of exercise modality.

Muscle wasting in cancer: opportunities and challenges for exercise in clinical cancer trials

BACKGROUND

Low muscle in cancer is associated with an increase in treatment-related toxicities and is a predictor of cancer-related and all-cause mortality. The mechanisms of cancer-related muscle loss are multifactorial, including anorexia, hypogonadism, anaemia, inflammation, malnutrition, and aberrations in skeletal muscle protein turnover and metabolism.

METHODS

In this narrative review, we summarise relevant literature to (i) review the factors influencing skeletal muscle mass regulation, (ii) provide an overview of how cancer/treatments negatively impact these, (iii) review factors beyond muscle signalling that can impact the ability to participate in and respond to an exercise intervention to counteract muscle loss in cancer, and (iv) provide perspectives on critical areas of future research.

RESULTS

Despite the well-known benefits of exercise, there remains a paucity of clinical evidence supporting the impact of exercise in cancer-related muscle loss. There are numerous challenges to reversing muscle loss with exercise in clinical cancer settings, ranging from the impact of cancer/treatments on the molecular regulation of muscle mass, to clinical challenges in responsiveness to an exercise intervention. For example, tumour-related/treatment-related factors (e.g. nausea, pain, anaemia, and neutropenia), presence of comorbidities (e.g. diabetes, arthritis, and chronic obstructive pulmonary disease), injuries, disease progression and bone metastases, concomitant medications (e.g., metformin), can negatively affect an individual's ability to exercise safely and limit subsequent adaptation.

CONCLUSIONS

This review identifies numerous gaps and oppportunities in the area of low muscle and muscle loss in cancer. Collaborative efforts between preclinical and clinical researchers are imperative to both understanding the mechanisms of atrophy, and develop appropriate therapeutic interventions.

Systematic Review of Exercise Studies in Persons with Multiple Sclerosis: Exploring the Quality of Interventions According to the Principles of Exercise Training

INTRODUCTION

The objective of this systematic review is to explore the application and reporting of (i) the principles of exercise training in exercise trials, (ii) the components of exercise prescription, and (iii) the adherence towards the prescribed programmes in randomised controlled trials (RCTs) in persons with multiple sclerosis (pwMS).

METHODS

The MEDLINE, CINAHL, SPORTDiscus, PubMed and Embase electronic databases were searched from 1 January 2000 to 16 October 2020. RCTs comprising at least 3 weeks of aerobic and/or resistance exercise intervention in pwMS that reported at least one physiological outcome and were published in peer-reviewed journals were eligible for inclusion.

RESULTS

Out of 52 RCTs included in this review, 58 intervention arms were examined. None applied more than four principles of exercise training. Specificity was addressed by 85%, progression by 33%, overload by 59%, initial values by 26%, reversibility by 0% and diminishing returns by 2% of trials. Fifty-two percent of trials reported all components of exercise prescription, and 3% of trials reported the level of adherence to the prescribed exercise.

CONCLUSION

This systematic review reveals that exercise training principles were not respected in the majority of included RCTs. The weak quality of reported exercise interventions limits the interpretation of the studies' results and potentially leads to an underestimation of 'exercise as medicine' in pwMS. Also, the vague descriptions of exercise prescription and adherence impede the reproducibility of results. Future studies must attend to all principles of exercise training and provide transparent information on the prescribed and performed programmes to develop specific and valid exercise recommendations for pwMS.

SYSTEMATIC REVIEW REGISTRATION

CRD42020162671, 28/04/2020, PROSPERO.

Attention to principles of exercise training: an updated systematic review of randomized controlled trials in cancers other than breast and prostate

BACKGROUND

The primary objective of this systematic review was to update our previous review on randomized controlled trials (RCTs) of exercise in cancers other than breast or prostate, evaluating: 1) the application of principles of exercise training within the exercise prescription; 2) reporting of the exercise prescription components (i.e., frequency, intensity, time, and type (FITT)); and 3) reporting of participant adherence to FITT. A secondary objective was to examine whether reporting of these interventions had improved over time.

METHODS

MEDLINE, EMBASE, CINAHL and SPORTDiscus databases were searched from 2012 to 2020. Eligible studies were RCTs of at least 4 weeks of aerobic and/or resistance exercise that reported on physiological outcomes relating to exercise (e.g., aerobic capacity, muscular strength) in people with cancer other than breast or prostate.

RESULTS

Eighty-six new studies were identified in the updated search, for a total of 107 studies included in this review. The principle of specificity was applied by 91%, progression by 32%, overload by 46%, initial values by 72%, reversibility by 7% and diminishing returns by 5%. A significant increase in the percentage of studies that appropriately reported initial values (46 to 80%, p < 0.001) and progression (15 to 37%, p = 0.039) was found for studies published after 2011 compared to older studies. All four FITT prescription components were fully reported in the methods in 58% of all studies, which was higher than the proportion that fully reported adherence to the FITT prescription components in the results (7% of studies). Reporting of the FITT exercise prescription components and FITT adherence did not improve in studies published after 2011 compared to older studies.

CONCLUSION

Full reporting of exercise prescription and adherence still needs improvement within exercise oncology RCTs. Some aspects of exercise intervention reporting have improved since 2011, including the reporting of the principles of progression and initial values. Enhancing the reporting of exercise prescriptions, particularly FITT adherence, may provide better context for interpreting study results and improve research to practice translation.

The Effect of Resistance Training on Body Composition During and After Cancer Treatment: A Systematic Review and Meta-Analysis

BACKGROUND

Changes in body composition during cancer treatments have been linked with poorer outcomes, and increased morbidity and mortality. The effect of resistance training (RT) on body composition in cancer cohorts is debated.

OBJECTIVE

We conducted a systematic review and meta-analysis to determine the effect of RT on body composition during and after treatment.

METHODS

We searched five electronic databases for articles up to 1 February 2021 and included randomized controlled trials that compared RT with a non-exercise control in adults with cancer. Risk of bias was assessed using the RoB 2 tool. Pairwise, random-effects meta-analysis was used to synthesize the available data.

RESULTS

Overall, we included 15 studies (n = 1368). After treatment (11 studies), RT increased lean mass with moderate heterogeneity {0.41 kg [95% confidence interval (CI) 0.05, 0.76], p = 0.029; I² = 47.1%, p = 0.02} and decreased fat mass with substantial heterogeneity (- 0.59 kg [95% CI - 1.05, - 0.12], p = 0.019; I² = 69.1%, p < 0.001). During treatment (4 studies), RT did not increase lean mass (0.71 kg [95% CI - 0.04, 1.45], p = 0.05; I² = 0.0%, p = 0.75) or reduce fat mass (0.00 kg [95% CI - 5.31, 5.30], p = 0.99; I² = 0.0%, p = 0.62), both with no heterogeneity.

CONCLUSION

Modest improvements in body composition were observed following RT after cancer treatment; however, no changes were observed during treatment. These adaptations are markedly lower than those observed in healthy cohorts but may be clinically meaningful for the cancer survivorship population. At present it is unclear if these diminished adaptations are due to ineffective exercise prescriptions in cancer cohorts or due to an innate anabolic resistance as a result of cancer and its treatments.

STUDY REGISTRATION

Open Science Framework (osf.io/x6z72).

Attention to the Principles of Exercise Training in Exercise Studies of Persons With Lung Cancer: A Systematic Review

The authors systematically reviewed and summarized exercise trials in persons with lung cancer on (a) attention to the principles of exercise training (specificity, progression, overload, initial values, reversibility, and diminishing returns); (b) methodological reporting of FITT (frequency, intensity, time, and type) components; and (c) reporting on participant adherence to prescribed FITT. Randomized controlled trials of exercise that reported on ≥1 physical fitness, physical function, or body composition outcome in persons with lung cancer were included. Of 20 trial arms, none incorporated all principles of exercise training. Specificity was included by 95%, progression by 45%, overload by 75%, and initial values by 80%, while one trial arm applied reversibility and diminishing returns. Fourteen interventions reported all FITT components; however, none reported adherence to each component. Including the principles of training and reporting FITT components will contribute to better understanding of the efficacy of exercise for persons with lung cancer and inform evidence-based exercise prescriptions.

Skeletal Muscle-Adipose Tissue-Tumor Axis: Molecular Mechanisms Linking Exercise Training in Prostate Cancer

Increased visceral adiposity may influence the development of prostate cancer (PCa) aggressive tumors and cancer mortality. White adipose tissue (WAT), usually referred to as periprostatic adipose tissue (PPAT), surrounds the prostatic gland and has emerged as a potential mediator of the tumor microenvironment. Exercise training (ET) induces several adaptations in both skeletal muscle and WAT. Some of these effects are mediated by ET-induced synthesis and secretion of several proteins, known as myo- and adipokines. Together, myokines and adipokines may act in an endocrine-like manner to favor communication between skeletal muscle and WAT, as they may work together to improve whole-body metabolic health. This crosstalk may constitute a potential mechanism by which ET exerts its beneficial role in the prevention and treatment of PCa-related disorders; however, this has not yet been explored. Therefore, we reviewed the current evidence on the effects of skeletal muscle–WAT–tumor crosstalk in PCa, and the potential mediators of this process to provide a better understanding of underlying ET-related mechanisms in cancer.

Training Load and Its Role in Injury Prevention, Part I: Back to the Future

The purpose of this 2-part commentary series is† to explain why we believe our ability to control injury risk by manipulating training load (TL) in its current state is an illusion and why the foundations of this illusion are weak and unreliable. In part 1, we introduce the training process framework and contextualize the role of TL monitoring in the injury-prevention paradigm. In part 2, we describe the conceptual and methodologic pitfalls of previous authors who associated TL and injury in ways that limited their suitability for the derivation of practical recommendations. The first important step in the training process is developing the training program: the practitioner develops a strategy based on available evidence, professional knowledge, and experience. For decades, exercise strategies have been based on the fundamental training principles of overload and progression. Training-load monitoring allows the practitioner to determine whether athletes have completed training as planned and how they have coped with the physical stress. Training load and its associated metrics cannot provide a quantitative indication of whether particular load progressions will increase or decrease the injury risk, given the nature of previous studies (descriptive and at best predictive) and their methodologic weaknesses. The overreliance on TL has moved the attention away from the multifactorial nature of injury and the roles of other important contextual factors. We argue that no evidence supports the quantitative use of TL data to manipulate future training with the purpose of preventing injury. Therefore, determining "how much is too much" and how to properly manipulate and progress TL are currently subjective decisions based on generic training principles and our experience of adjusting training according to an individual athlete's response. Our message to practitioners is to stop seeking overly simplistic solutions to complex problems and instead embrace the risks and uncertainty inherent in the training process and injury prevention.

Supported progressive resistance exercise training to counter the adverse side effects of robot-assisted radical prostatectomy: a randomised controlled trial

PURPOSE

To investigate the effects of a supported home-based progressive resistance exercise training (RET) programme on indices of cardiovascular health, muscular strength and health-related quality of life (HR-QoL) in prostate cancer (PCa) patients after treatment with robot-assisted radical prostatectomy (RARP).

METHODS

This study was a single-site, two-arm randomised controlled trial, with 40 participants randomised to either the intervention or control group over a 10-month period. In addition to receiving usual care, the intervention group completed three weekly RET sessions using resistance bands for 6 months. Participants performed 3 sets of 12-15 repetitions for each exercise, targeting each major muscle group. The control group received usual care only. Brachial artery flow-mediated dilatation (FMD) was the primary outcome and assessed at baseline, 3 and 6 months. Secondary outcomes included body weight, body fat, aerobic fitness, strength and blood-borne biomarkers associated with cardiometabolic risk.

RESULTS

There was no significant difference between the groups in FMD at 3 or 6 months. However, there were improvements in aerobic exercise capacity (P < 0.01) and upper- (P < 0.01) and lower-limb (P = 0.01) strength in favour of the RET group at 6 months, accompanied by greater weight loss (P = 0.04) and a reduction in body fat (P = 0.02). Improvements in HRQoL were evident in the RET group at 3 and 6 months via the PCa-specific component of the FACT-P questionnaire (both P < 0.01). Five adverse events and one serious adverse event were reported throughout the trial duration.

CONCLUSION

This study demonstrates that home-based RET is an effective and safe mode of exercise that elicits beneficial effects on aerobic exercise capacity, muscular strength and HR-QoL in men who have undergone RARP.

TRIAL REGISTRATION

ISRCTN10490647.

i-CONTENT tool for assessing therapeutic quality of exercise programs employed in randomised clinical trials

OBJECTIVE

When appraising the quality of randomised clinical trial (RCTs) on the merits of exercise therapy, we typically limit our assessment to the quality of the methods. However, heterogeneity across studies can also be caused by differences in the quality of the exercise interventions (ie, 'the potential effectiveness of a specific intervention given the potential target group of patients')-a challenging concept to assess. We propose an internationally developed, consensus-based tool that aims to assess the quality of exercise therapy programmes studied in RCTs: the international Consensus on Therapeutic Exercise aNd Training (i-CONTENT) tool.

METHODS

Forty-nine experts (from 12 different countries) in the field of physical and exercise therapy participated in a four-stage Delphi approach to develop the i-CONTENT tool: (1) item generation (Delphi round 1), (2) item selection (Delphi rounds 2 and 3), (3) item specification (focus group discussion) and (4) tool development and refinement (working group discussion and piloting).

RESULTS

Out of the 61 items generated in the first Delphi round, consensus was reached on 17 items, resulting in seven final items that form the i-CONTENT tool: (1) patient selection; (2) qualified supervisor; (3) type and timing of outcome assessment; (4) dosage parameters (frequency, intensity, time); (5) type of exercise; (6) safety of the exercise programme and (7) adherence to the exercise programme.

CONCLUSION

The i-CONTENT-tool is a step towards transparent assessment of the quality of exercise therapy programmes studied in RCTs, and ultimately, towards the development of future, higher quality, exercise interventions.

Exercise Guidelines for Cancer Survivors: Consensus Statement from International Multidisciplinary Roundtable

PURPOSE

The number of cancer survivors worldwide is growing, with over 15.5 million cancer survivors in the United States alone-a figure expected to double in the coming decades. Cancer survivors face unique health challenges as a result of their cancer diagnosis and the impact of treatments on their physical and mental well-being. For example, cancer survivors often experience declines in physical functioning and quality of life while facing an increased risk of cancer recurrence and all-cause mortality compared with persons without cancer. The 2010 American College of Sports Medicine Roundtable was among the first reports to conclude that cancer survivors could safely engage in enough exercise training to improve physical fitness and restore physical functioning, enhance quality of life, and mitigate cancer-related fatigue.

METHODS

A second Roundtable was convened in 2018 to advance exercise recommendations beyond public health guidelines and toward prescriptive programs specific to cancer type, treatments, and/or outcomes.

RESULTS

Overall findings retained the conclusions that exercise training and testing were generally safe for cancer survivors and that every survivor should "avoid inactivity." Enough evidence was available to conclude that specific doses of aerobic, combined aerobic plus resistance training, and/or resistance training could improve common cancer-related health outcomes, including anxiety, depressive symptoms, fatigue, physical functioning, and health-related quality of life. Implications for other outcomes, such as peripheral neuropathy and cognitive functioning, remain uncertain.

CONCLUSIONS

The proposed recommendations should serve as a guide for the fitness and health care professional working with cancer survivors. More research is needed to fill remaining gaps in knowledge to better serve cancer survivors, as well as fitness and health care professionals, to improve clinical practice.

Analysis of reporting completeness in exercise cancer trials: a systematic review

Background

Exercise is an effective therapeutic intervention for cancer survivors. Concerns about the completeness of reporting of exercise interventions have been raised in the literature, but without any formal analysis. This study aimed to evaluate the completeness of reporting of exercise interventions for cancer survivors in a large sample of randomized clinical trials (RCTs).

Methods

We developed a pre-defined protocol. We searched MEDLINE, EMBASE, and CENTRAL for exercise trials in oncology between 2010 and 2017. Pairs of independent researchers screened the records, extracted study characteristics, and assessed 16 items on the TIDieR checklist (i.e., the 12 items, with item 5 divided into two and item 8 divided into four). For each of these items, the percentage of interventions in the included studies that reported the item was calculated.

Results

We included 131 RCTs reporting 138 interventions in the analysis. Breast cancer was the most common type of cancer (69, 50%), and aerobic exercise was the most studied exercise modality (43, 30%) followed by combined aerobic and resistance training (40, 28%). Completeness of reporting ranged from 42 to 96% among the TIDieR items; none of the items was fully reported. ‘Intervention length’ was the most reported item across interventions (133, 96%), followed by ‘rationale’ (131, 95%), whereas ‘provider’ (58, 42%) and ‘how well (planned)’ (63, 46%) were the two least reported items. Half of the TIDieR items were completely reported in 50 to 70% of the interventions, and only four items were reported in more than 80% of the interventions (Items 2 and 8a to c). The seven items deemed to be core for replication (Items 3 to 9) exhibited a mean reporting of 71%, ranging from 42 to 96%.

Conclusion

Exercise training interventions for cancer survivors are incompletely reported across RCTs published between 2010 and 2017. The reporting of information about the provider, materials, and modifications require urgent improvements. Stronger reporting will enhance usability of trial reports by both healthcare providers and survivors, and will help to reduce research waste.