BackgroundThe purpose of this study was  to identify demographic, clinical, psychosocial, physical and environmental factors that are associated with participation in and adherence to a combined resistance and endurance exercise program among cancer survivors, shortly after completion of primary cancer treatment. Data from the randomized controlled Resistance and Endurance exercise After ChemoTherapy (REACT) study were used for this study.MethodsThe participants of the REACT study were randomly allocated to either a high intensity (HI) or low-to-moderate intensity (LMI) exercise program. Patients’ participation rate was defined as the cancer survivors’ decision to participate in the REACT study. Exercise adherence reflected participants’ attendance to the scheduled exercise sessions and their compliance to the prescribed exercises. High session attendance rates were defined as attending at least 80 % of the sessions. High compliance rates were defined as performing at least of 90 % of the prescribed exercise across all sessions. Correlates of exercise adherence were studied separately for HI and LMI exercise. Demographic, clinical, and physical factors were assessed using self-reported questionnaires. Relevant clinical information was extracted from medical records. Multivariable logistic regression analyses were applied to identify correlates that were significantly associated with participation, high session attendance, high compliance with resistance and high compliance with endurance exercises.ResultsParticipants were more likely to have higher education, be non-smokers, have lower psychological distress, higher outcome expectations, and perceive more exercise barriers than non-participants. In HI exercise, higher self-efficacy was significantly associated with high session attendance and high compliance with endurance exercises, and lower psychological distress was significantly associated with high compliance with resistance exercises. In LMI exercise, being a non-smoker was significantly associated with high compliance with resistance exercises and higher BMI was significantly associated with high compliance with resistance and endurance exercises. Furthermore, breast cancer survivors were less likely to report high compliance with resistance and endurance exercises in LMI exercise compared to survivors of other types of cancer. The discriminative ability of the multivariable models ranged from 0.62 to 0.75.ConclusionSeveral demographic, clinical and psychosocial factors were associated with participation in and adherence to exercise among cancer survivors. Psychosocial factors were more strongly associated with adherence in HI than LMI exercise.Trial registrationThis study was registered at the Netherlands Trial Register [NTR2153] on the 5th of January 2010.

BackgroundIn the earlier randomized controlled Physical Activity during Cancer Treatment (PACT) study, we found beneficial effects of an 18-week supervised exercise program on fatigue in patients with newly diagnosed breast or colon cancer undergoing adjuvant treatment. The present study assessed long-term effects of the exercise program on levels of fatigue and physical activity 4 years after participation in the PACT study.MethodsThe original study was a two-armed, multicenter randomized controlled trial comparing an 18-week supervised exercise program to usual care among 204 breast cancer patients and 33 colon cancer patients undergoing adjuvant treatment. Of the 237 PACT participants, 197 participants were eligible and approached to participate in the 4-year post-baseline measurements, and 128 patients responded. We assessed fatigue and physical activity levels at 4 years post-baseline and compared this to levels at baseline, post-intervention (18 weeks post-baseline), and at 36 weeks post-baseline.ResultsIntention-to-treat mixed linear effects model analyses showed that cancer patients in the intervention group reported significantly higher moderate-to-vigorous total physical activity levels (141.46 min/week (95% confidence interval (CI) 1.31, 281.61, effect size (ES) = 0.22) after 4 years compared to the usual care group. Furthermore, cancer patients in the intervention group tended to experience less physical fatigue at 4 years post-baseline compared to the usual care group (− 1.13, 95% CI –2.45, 0.20, ES = 0.22), although the result was not statistically significant.ConclusionPatients with breast or colon cancer who participated in the 18-week exercise intervention showed significant higher levels of moderate-to-vigorous total physical activity levels and a tendency towards lower physical fatigue levels 4 years post-baseline. Our result indicate that exercising during chemotherapy is a promising strategy for minimizing treatment-related side effects, both short and long term.Trial registrationCurrent Controlled Trials ISRCTN43801571, Dutch Trial Register NTR2138. Trial registered on 9 December 2009.

Background Up to 60% of breast cancer patients treated with chemotherapy is confronted with cognitive problems, which can have a significant impact on daily activities and quality of life (QoL). We investigated whether exercise training improves cognition in chemotherapy-exposed breast cancer patients 2–4 years after diagnosis. Methods Chemotherapy-exposed breast cancer patients, with both self-reported cognitive problems and lower than expected performance on neuropsychological tests, were randomized to an exercise or control group. The 6-month exercise intervention consisted of supervised aerobic and strength training (2 h/week), and Nordic/power walking (2 h/week). Our primary outcome was memory functioning (Hopkins Verbal Learning Test-Revised; HVLT-R). Secondary outcomes included online neuropsychological tests (Amsterdam Cognition Scan; ACS), self-reported cognition (MD Anderson Symptom Inventory for multiple myeloma; MDASI-MM), physical fitness (relative maximum oxygen uptake; VO2peak), fatigue (Multidimensional Fatigue Inventory), QoL (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire; EORTC QLQ C-30), depression (Patient Health Questionnaire-9, Hospital Anxiety and Depression Scale; HADS), and anxiety (HADS). HVLT-R total recall was analyzed with a Fisher exact test for clinically relevant improvement (≥ 5 words). Other outcomes were analyzed using multiple regression analyses adjusted for baseline and stratification factors. Results We randomized 181 patients to the exercise (n = 91) or control group (n = 90). Two-third of the patients attended ≥ 80% of the exercise sessions, and physical fitness significantly improved compared to control patients (B VO2peak 1.4 ml/min/kg, 95%CI:0.6;2.2). No difference in favor of the intervention group was seen on the primary outcome. Significant beneficial intervention effects were found for self-reported cognitive functioning [MDASI-MM severity (B-0.7, 95% CI − 1.2; − 0.1)], fatigue, QoL, and depression. A hypothesis-driven analysis in highly fatigued patients showed positive exercise effects on tested cognitive functioning [ACS Reaction Time (B-26.8, 95% CI − 52.9; − 0.6) and ACS Wordlist Learning (B4.4, 95% CI 0.5; 8.3)]. Conclusions A 6-month exercise intervention improved self-reported cognitive functioning, physical fitness, fatigue, QoL, and depression in chemotherapy-exposed breast cancer patients with cognitive problems. Tested cognitive functioning was not affected. However, subgroup analysis indicated a positive effect of exercise on tested cognitive functioning in highly fatigued patients. Trial Registration Netherlands Trial Registry: Trial NL5924 (NTR6104). Registered 24 October 2016, https://www.trialregister.nl/trial/5924.

Purpose Maintaining high adherence rates (session attendance and compliance) in exercise programs during breast cancer treatment can be challenging. We aimed to identify adherence rates and predictors to an exercise program during adjuvant breast cancer treatment. Methods Ninety-two patients with localized breast cancer undergoing chemotherapy were randomly assigned to an 18-week supervised moderate-to-high intensity aerobic and resistance exercise program, including two 1-hour sessions/week. Additionally, participants were asked to be physically active for at least 30 minutes/day on at least three other days. We report median percentages for attendance, compliance with the prescribed duration and intensity of aerobic and muscle strength exercises, and the exercise advice given. Predictors included in univariate and multivariable linear regression models were demographical, tumor- and treatment-related factors, constructs of the theory of planned behavior, psychological and physical factors. Results Patients attended 83% (interquartile range: 69–91%) of the supervised sessions. Compliance with the duration of aerobic exercise, high-intensity aerobic exercise (cycling at the ventilatory threshold), muscle strength exercises and the exercise advice were 88%(64–97%), 50%(22–82%), 84%(65–94%) and 61%(33%–79%), respectively. Education, radiotherapy, BMI and physical fatigue were important predictors of adherence to supervised exercise. Beliefs about planned behaviors were important predictors, especially for compliance with the exercise advice. Conclusions Attendance to and compliance with an 18-week aerobic and strength exercise program were high. The lowest compliance was found for high-intensity supervised aerobic exercise. The identified predictors should be considered when designing or adapting exercise programs for patients with localized breast cancer to increase adherence. Trial registration Current Controlled Trials ISRCTN43801571 Dutch Trial Register NTR2138