Effect of supervised exercise on aerobic capacity in cancer survivors: Adherence and workload predict variance in effect

A Review on the Role of Exercise Training to Prevent a Decline in Cardiorespiratory Fitness and Cardiac Function in Breast Cancer Survivors

PURPOSE

Improvements in diagnosis and treatment mean that the long-term health of breast cancer survivors (BCS) is increasingly dictated by cardiovascular comorbidities. This is partly a consequence of exposure to cardiotoxic therapies, which result in cardiac dysfunction and decreased cardiorespiratory fitness (CRF). Exercise training (ExT) is a key therapeutic strategy for secondary prevention and increasing CRF in adults with established cardiovascular disease. Exercise-based cardio-oncology rehabilitation (CORE) has been proposed as an emerging strategy to address CRF and cardiac impairment in BCS. This review aims to (1) provide an overview of the impact of breast cancer therapy on CRF; (2) provide an up-to-date summary of the effects of ExT on CRF and cardiac function in BCS undergoing cardiotoxic therapy; and (3) discuss how traditional ExT approaches can be adapted for BCS undergoing therapy.

REVIEW METHODS

A literature review was performed based on an intensive literature search for systematic reviews and meta-analyses, randomized and non-randomized controlled trials and single-arm trials investigating the impact of exercise training or cardiac rehabilitation on CRF and/or cardiac function in BCS who are undergoing or have completed cardiotoxic cancer therapy.

SUMMARY

Overall, current evidence suggests that ExT induces clinically meaningful benefits for CRF in BCS during and after therapy. There is also emerging evidence that ExT can improve peak exercise measures of cardiac function; however, there is a need for further research to understand how to adapt these effective ExT approaches into clinical CORE-based settings.

Is functional training an efficient approach to improve body composition in older people? A systematic review

Introduction: Increases in fat mass and reductions in lean mass are associated with the frailty and mortality of older people. In this context, Functional Training (FT) is an option to increase lean mass and reduce fat mass in older people. Thus, this systematic review aims to investigate the effects of FT on body fat and lean mass in older people. Methods: We included randomized controlled clinical trials, with at least one intervention group that employed FT, with the age of participants ≥60 years; and participants physically independent and healthy. We performed the systematic investigation in Pubmed MEDLINE, Scopus, Web of Science, Cochrane Library, and Google Scholar. We extracted the information and used the PEDro Scale to assess the methodological quality of each study. Results: Our research found 3,056 references with five appropriate studies. Of the five studies, three presented reductions in fat mass, all of them with interventions between three and 6 months, different training dose parameters, and 100% of the sample was composed of women. On the other hand, two studies with interventions between 10 and 12 weeks presented conflicting results. Conclusion: Despite the limited literature about lean mass, it appears that long-term FT interventions may reduce fat mass in older women. Clinical Trial Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=399257, identifier CRD42023399257.

Feasibility of Implementing Cancer-Specific Community-Based Exercise Programming: A Multi-Centre Randomized Trial

BACKGROUND

There is growing recognition of the importance of reporting preliminary work on the feasibility of a trial. The present study aimed to assess the feasibility of (1) a proposed fitness testing battery, and (2) processes related to the implementation of cancer-specific exercise programming in a community setting.

METHODS/DESIGN

A randomized controlled implementation feasibility trial was performed in advance of a large-scale implementation study. Eligible participants within 18 months of a cancer diagnosis were randomized to immediate or delayed community-based exercise at YMCA locations in Calgary and Edmonton, Canada for an 8-week period. The primary outcome for the trial was the feasibility of the physical fitness testing battery, defined as a 70% or greater completion rate across the 24-week study period. The Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) framework was used to evaluate processes related to implementation of the exercise program across the two sites.

RESULTS

Eighty participants were recruited, 73 (91%) completed the 8-week trial, and 68 (85%) completed the 16- and 24-week follow-ups. Sixty participants (75%) completed the full physical fitness test battery at each time point, and 59 (74%) completed the patient-reported outcome measures. Statistically significant between-group differences were found in favor of the exercise group for functional aerobic capacity, upper and lower extremity strength, and symptoms. Differences were found between the sites, however, in completion rates and processes related to program implementation.

DISCUSSION

Findings suggest the need for minor adaptations to the physical fitness battery and outcome measures to better fit the community context. While findings support feasibility, context-specific challenges related to implementation processes were identified.

Key Factors Associated with Adherence to Physical Exercise in Patients with Chronic Diseases and Older Adults: An Umbrella Review

Physical inactivity is a major concern and poor adherence to exercise programs is often reported. The aim of this paper was to systematically review published reviews on the study of adherence to physical exercise in chronic patients and older adults and to identify those adherence-related key factors more frequently suggested by reviews for that population. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Results were classified considering the target population and participants' characteristics to identify the most repeated factors obtained for each condition. Fifty-five articles were finally included. Fourteen key factors were identified as relevant to increase adherence to physical exercise by at least ten reviews: (a) characteristics of the exercise program, (b) involvement of professionals from different disciplines, (c) supervision, (d) technology, (e) initial exploration of participant's characteristics, barriers, and facilitators, (f) participants education, adequate expectations and knowledge about risks and benefits, (g) enjoyment and absence of unpleasant experiences, (h) integration in daily living, (i) social support and relatedness, (j) communication and feedback, (k) available progress information and monitoring, (l) self-efficacy and competence, (m) participant's active role and (n) goal setting. Therefore, adherence to physical exercise is affected by several variables that can be controlled and modified by researchers and professionals.

Aerobic exercise and cardiopulmonary fitness in childhood cancer survivors treated with a cardiotoxic agent: a meta-analysis

PURPOSE

The main purpose of this review was to synthesize evidence from existing childhood cancer survivor studies that report the effect of aerobic exercise on cardiopulmonary fitness (a marker of cardiovascular health), in survivors that were currently receiving or had been treated with a cardiotoxic agent.

METHODS

Studies were identified for this review by searching both electronic databases of peer-reviewed articles, as well as various sources of gray literature. Risk of bias was qualitatively assessed in these studies using the domains outlined in the Cochrane Handbook for Systematic Reviews of Interventions. Data was analyzed quantitatively using random-effects meta-analyses and subgroup analyses in RevMan Software.

RESULTS

Meta-analysis of pooled evidence from the nine included studies suggests that aerobic exercise has a statistically and clinically significant positive effect on cardiopulmonary fitness (effect estimate = 6.92%, p value = 0.02). Findings from subgroup analyses of clinical characteristics and exercise parameters were not significant.

CONCLUSIONS

The findings from this review, although not directly demonstrating a cardioprotective effect, are a preliminary step towards establishing the putative cardioprotective effect of aerobic exercise against the direct cardiotoxic impact of cancer treatments. The significant positive effect estimate in favor of aerobic exercise is a small but important advancement towards the standardization of aerobic exercise in childhood cancer survivors. Further studies are necessary.

Meta-analysis of Exercise Training on Vascular Endothelial Function in Cancer Survivors

Cancer and cardiovascular disease (CVD) are leading causes of morbidity and mortality in the United States. Vascular endothelial dysfunction, an important contributor in the development of CVD, improves with exercise training in patients with CVD. However, the role of regular exercise to improve vascular function in cancer survivors remains equivocal. We performed a meta-analysis to determine the effect of exercise training on vascular endothelial function in cancer survivors. We searched PubMed (1975 to 2016), EMBASE CINAHL (1937 to 2016), OVID MEDLINE (1948 to 2016), and Cochrane Central Registry of Controlled Trials (1991 to 2016) using search terms: vascular function, endothelial function, flow-mediated dilation [FMD], reactive hyperemia, exercise, and cancer. Studies selected were randomized controlled trials of exercise training on vascular endothelial function in cancer survivors. We calculated pooled effect sizes and performed a meta-analysis. We identified 4 randomized controlled trials (breast cancer, n=2; prostate cancer, n=2) measuring vascular endothelial function by FMD (n=3) or reactive hyperemia index (n=1), including 163 cancer survivors (exercise training, n=82; control, n=81). Aerobic exercise training improved vascular function (n=4 studies; standardized mean difference [95% CI]=0.65 [0.33, 0.96], I²=0%; FMD, weighted mean difference [WMD]=1.28 [0.22, 2.34], I²=23.2%) and peak exercise oxygen uptake (3 trials; WMD [95% CI]=2.22 [0.83, 3.61] mL/kg/min; I²=0%). Our findings indicate that exercise training improves vascular endothelial function and exercise capacity in breast and prostate cancer survivors.

Lifestyle Interventions to Improve Cardiorespiratory Fitness and Reduce Breast Cancer Recurrence

As patients are living longer after a cancer diagnosis, survivorship is becoming increasingly important in cancer care. The sequelae of multimodality therapies include weight gain and decreased cardiorespiratory fitness, which increase cardiovascular risk. Evidence suggests that physical activity reduces the risk of breast cancer recurrence and death. Avoidance of weight gain after therapy also improves outcomes after a diagnosis of breast cancer. Prospective randomized trials must be performed to determine the benefits of specific physical activity and dietary habits for survivors of breast cancer. This review outlines the important physiologic changes that occur with antineoplastic therapy and the important role of exercise and diet.

Pathophysiology of exercise intolerance in breast cancer survivors with preserved left ventricular ejection fraction

Breast cancer (BC) survival rates have improved during the past two decades and as a result older BC survivors are at increased risk of developing heart failure (HF). Although the HF phenotype common to BC survivors has received little attention, BC survivors have a number of risk factors associated with HF and preserved ejection fraction (HFPEF) including older age, hypertension, obesity, metabolic syndrome and sedentary lifestyle. Moreover, not unlike HFPEF, BC survivors with preserved left ventricular ejection fraction (BCPEF) have reduced exercise tolerance measured objectively as decreased peak oxygen uptake (peak VO₂). This review summarizes the literature regarding the mechanisms of exercise intolerance and the role of exercise training to improve peak VO₂ in BCPEF.