Cardio-oncology · Aug 11, 2026

EXERT-BCHC: a prospective study of exercise regimens after breast cancer to improve skeletal muscle hypertrophy and conditioning

By Champ CE, Peluso C, Sulpizio D et al.

PURPOSE: As increased muscle mass and decreased fat mass are associated with improved survival after breast cancer treatment, herein we compare two regimens for conditioning and skeletal muscle hypertrophy (SMH) to assess their impact on body composition and VO2 max. METHODS: Fifteen participants were prospectively assessed during four exercise regimens for changes in body composition and VO2 max before and after each regimen. Participants underwent four weeks of conditioning, followed by four weeks of SMH training. After a four-week washout period, they underwent conditioning followed by SMH. RESULTS: In total, 15 participants completed the 20-week regimen. Prior to enrollment, all participants had previously completed at least 3 months of supervised, dose-escalated resistance training, with ongoing pre-regimen resistance training for median duration of 11.32 months (IQR). Median age at enrollment was 51 years, with 73% of participants having stage I-II breast cancer. Most patients underwent mastectomy (60%), surgical axillary management via sentinel lymph node biopsy (73%), adjuvant radiation therapy (60%), anti-estrogen systemic therapy (73%), and had not completed any prior cytotoxic systemic therapy (67%). 13% of participants had baseline lymphedema. During completion of the regimen, while all participants experienced muscle soreness, no adverse events were otherwise reported. From baseline through regimen month 5, increases in muscle mass and decreases in body fat were observed, though did not meet statistical significance. SMH-focused exercise blocks, in comparison to conditioning blocks, were associated with non-significant trends toward greater VO2 max (p = 0.068) and metabolism (p = 0.417). CONCLUSION: SMH-focused resistance training regimens, which uniquely optimize muscle mass, combat sarcopenia, improve balance and coordination, and enhance bone density, do not appear less efficacious than conditioning-focused regimens with respect to metabolism or VO₂ max. TRIAL REGISTRATION: ClinicalTrials.gov NCT07023887, registered 6/5/2025.

doi.org/10.1186/s40959-026-00551-6 Open access PubMed 42995645 Interventions