Scott JM, Thomas SM, Peppercorn JM, et al. - Researchers undertook a parallel-group randomized trial with patients with posttreatment primary breast cancer, to determine the tolerability as well as the efficacy of 2 exercise training dose regimens on cardiorespiratory fitness and patient-reported outcomes in this patient population. Random assignment of 174 postmenopausal patients (2.8 years post-adjuvant therapy) with impaired peak oxygen consumption (VO₂peak) was done to 1 of 2 supervised exercise training interventions delivered with a standard linear (LET) (fixed dose intensity per session for 160 min/wk) or nonlinear (NLET) (variable dose intensity per session for ≈120 min/wk) schedule relative to a stretching attention control group for 16 consecutive weeks. They found a rise in VO₂peak in LET and NLET, which was 0.6 ± 1.7 mL O₂·kg⁻¹·min⁻¹ and 0.8 ± 1.8 mL O₂·kg⁻¹·min⁻¹, respectively, compared with attention control, in the intention-to-treat analysis. Relative to attention control, NLET caused an improvement in all patient-reported outcomes. Overall, among patients previously treated for early-stage breast cancer, modest improvements in cardiorespiratory fitness were observed in correlation with short-term exercise training, independently of the dosing schedule.