Impact of Exercise on Chemotherapy Tolerance and Survival in Early-Stage Breast Cancer: A Nonrandomized Controlled Trial.

BACKGROUND: Available preliminary evidence is conflicting on whether exercise can positively influence antineoplastic treatment tolerance and in turn improve survival. PATIENTS AND METHODS: This study compared chemotherapy treatment tolerance and survival among women receiving adjuvant chemotherapy for early-stage breast cancer who participated in a single-arm trial of supervised aerobic and resistance exercise programming versus a historical cohort that did not receive structured exercise programming. RESULTS: The exercise group (EX; n=73) and control group (CTR; n=85) participants were matched on age and treatment and balanced on medical history, cancer diagnosis, and body mass index. Attendance in the EX group was 64% ± 27% of 3 offered sessions per week. For all chemotherapy agents combined, the relative risk (RR) of a chemotherapy dose reduction (RR, 0.78; 95% CI, 0.54-1.11) or delay (RR, 1.05; 95% CI, 0.62-1.80) did not differ between groups. However, the EX group had reduced relative and absolute risks of a dose reduction in doxorubicin by 60% and 18%, respectively. For all agents combined, there were no differences between groups in risk of anemia, neutropenia, or weight gain. In the EX group, dose reductions due to neutropenia (P=.027), other infections (P=.049), and fatigue (P=.037) were less common, whereas mucositis was more common (P=.023), compared with the CTR group. The EX group had reduced relative and absolute risks of weight gain on the docetaxel + cyclophosphamide regimen by 38% and 30%, respectively. After a median follow-up of 70 months (range, 54-84 months), there was no difference between the EX and CTR groups in disease-free survival events (n=8 [11%] vs n=9 [11%], respectively; log-rank test, P=.78) or overall survival events (n=5 [7%] vs n=6 [7%], respectively; log-rank test, P=.974). CONCLUSIONS: Overall, exercise programming during adjuvant chemotherapy does not appear to impact treatment tolerance or survival in women receiving common modern regimens of adjuvant chemotherapy for early-stage breast cancer. However, exercise may provide selective benefits, depending on the treatment regimen received.

Maintenance of Fitness and Quality-of-Life Benefits From Supervised Exercise Offered as Supportive Care for Breast Cancer.

BACKGROUND: Overwhelming randomized controlled trial evidence demonstrates that exercise has positive health impacts during and after treatment for breast cancer. Yet, evidence generated by studies in which exercise programs are delivered outside a tightly controlled randomized trial setting is limited. The purpose of this study was to assess the effectiveness of an evidence-based exercise program with real-world implementation on physical fitness and quality of life (QoL). PATIENTS AND METHODS: Oncologists referred women with early-stage breast cancer who were scheduled to receive adjuvant chemotherapy. The program consisted of supervised aerobic and resistance exercise of moderate to vigorous intensity 3 times per week until the end of treatment (chemotherapy ± radiotherapy), then twice per week for 10 weeks, followed by once per week for 10 weeks. Health-related physical fitness and QoL were assessed at baseline, end of treatment, end of program, and 1-year follow-up. RESULTS: A total of 73 women were enrolled. Estimated peak VO2 (VO2peak), QoL, and body weight were maintained between baseline and end of treatment, whereas muscular strength improved (P<.01). By the end of the program, VO2peak, heart rate recovery, waist circumference, and some aspects of QoL were improved (all P<.01) relative to baseline. One year later, VO2peak, QoL, and waist circumference were maintained relative to end of program, whereas the improvements in strength and heart rate recovery had dissipated (all P<.01). CONCLUSIONS: Evidence-based exercise programming delivered with real-world implementation maintained VO2peak, strength, and QoL during adjuvant treatment and improved these measures after treatment completion among women with breast cancer. Continued guidance and support may be required for long-term maintenance of strength improvements in this population.

The influence of race length on arterial compliance following an ultra-endurance marathon.

There is inconclusive evidence concerning the effects of routine participation in ultra-endurance events on cardiovascular disease (CVD) risk. Arterial compliance is a reliable, non-invasive, and effective tool for evaluating CVD risk. The purpose of this research was to examine if race length influences acute changes in arterial compliance following an ultra-marathon event. A total of 46 ultra-marathon runners were recruited including 21 participants (39.8 ± 8.3 years, 6 females) in the 80-km event and 25 participants (43.7 ± 9.8 years, 3 female) in the 195-km event. Arterial compliance was measured via radial applanation tonometry (CR-2000, HDI) for diastolic pulse contour analysis before and following the race. Significant between-group differences were found for changes in large arterial compliance with a decrease (increase in stiffness) following the 195-km event and an increase following the 80-kilometre event (p < .05). Longer race lengths are associated with greater reductions in large arterial compliance following recreational ultra-marathon running. Assessment of arterial compliance might be a useful prognostic tool to assess the long-term risk of CVD among ultra-marathon runners.