Bohovicova L; Masaryk Memorial Cancer Institute, Brno, Czech Republic.
Sumberova K; Buresova I; Palacova M; et al

Scientific Reports. 16(1), 2026 May 07.

Background
Breast cancer survivors are at increased risk of cardiovascular and
autonomic dysfunction following adjuvant chemotherapy, and exercise
interventions may help mitigate these effects. This randomized prospective
study evaluated the effects of a supervised, online-delivered exercise
intervention on cardiorespiratory fitness, cardiac autonomic modulation,
body composition, and quality of life in breast cancer survivors after
chemotherapy.
Methods
Seventy-two women were allocated to an exercise group or
usual care. The intervention consisted of a 12-week home-based exercise
program conducted online, with aerobic intensity individualized to 60-80%
of peak oxygen uptake. Cardiorespiratory fitness was assessed using
cardiopulmonary exercise testing and the 6-min walk test, while heart rate
variability was monitored longitudinally and analyzed using linear
mixed-effects models. Body composition and patient-reported outcomes were
assessed at baseline, post-chemotherapy, and post-intervention.
Results
The online supervised exercise resulted in a significant improvement in peak oxygen
uptake (+ 2.1 ml kg-1 min-1), which exceeded changes observed in the
control group (p = 0.009). Improvements in 6-min walk distance and
recovery of heart rate variability occurred irrespective of group
allocation. Changes in body composition, quality of life and the
improvement of heart rate variability metrics did not differ between
groups.