Adherence And Attendance During Versus After Chemotherapy In Exercise Influence On Taxane Side Effects

Abstract

Exercise throughout cancer treatment can positively affect clinical and patient-reported outcomes. However, adverse side effects (e.g. fatigue) may reduce exercise adherence during chemotherapy. To potentially further improve patient prognosis, developing strategies to maximize exercise participation across the cancer treatment trajectory is warranted. PURPOSE: To compare adherence and attendance to a supervised multimodal exercise intervention completed during chemotherapy for breast cancer to the same intervention completed after chemotherapy..| METHODS: Women with stage I-III breast cancer were randomized to: 1) immediate exercise during chemotherapy (IE); or 2) delayed exercise after chemotherapy (DE). The exercise intervention matched the length of each participant’s chemotherapy regime (8-12 wks) and included 3x/wk supervised aerobic (50-75% HRR, 30-35 min), resistance (1-2 sets, 10-12 reps, 50-65% estimated 1-RM), and balance training. Mean attendance and adherence to aerobic (i.e. intensity/duration) and resistance (i.e. sets/reps) exercise were calculated. Exercise trainers recorded reasons for missed sessions. RESULTS: 26 women enrolled and attended ≥1 session (IE: n=12, DE: n=14). Attendance did not differ between groups (IE=79±24%, DE=81±21%, p=0.82). No group differences were found for adherence to aerobic duration (IE=94±12%, DE=98±2%, p=0.28) or intensity (IE=78±30%, DE=82±17%, p=0.64), or resistance training (IE=73±35%, DE=90±9%, p=0.13). Among IE participants, top reasons for missed sessions were treatment-related symptoms (38%) (i.e. fatigue) and non-treatment related illness (17%) (i.e. cold/flu). Missed sessions for the DE group were most often due to non-treatment-related injury (43%) and travel (23%). CONCLUSION: Adherence to an identical supervised exercise intervention did not vary based on whether it was completed during or after chemotherapy. Barriers to attendance differed by group, thus strategies to maximize exercise participation during chemotherapy should be unique to the time of intervention delivery. Although feasibility does not appear to vary by timing relative to treatment, further analysis is required to determine if the timepoint of exercise delivery has differing effects on physical and psychological benefits.