Monitoring training progress during exercise training in cancer survivors: a submaximal exercise test as an alternative for a maximal exercise test?

OBJECTIVE To examine the use of a submaximal exercise test in detecting change in fitness level after a physical training program, and to investigate the correlation of outcomes as measured submaximally or maximally. DESIGN A prospective study in which exercise testing was performed before and after training intervention. SETTING Academic and general hospital and rehabilitation center. PARTICIPANTS Cancer survivors (N=147) (all cancer types, medical treatment completed > or =3 mo ago) attended a 12-week supervised exercise program. INTERVENTIONS A 12-week training program including aerobic training, strength training, and group sport. MAIN OUTCOME MEASURES Outcome measures were changes in peak oxygen uptake (Vo(2)peak) and peak power output (both determined during exhaustive exercise testing) and submaximal heart rate (determined during submaximal testing at a fixed workload). RESULTS The Vo(2)peak and peak power output increased and the submaximal heart rate decreased significantly from baseline to postintervention (P<.001). Changes in submaximal heart rate were only weakly correlated with changes in Vo(2)peak and peak power output. Comparing the participants performing submaximal testing with a heart rate less than 140 beats per minute (bpm) versus the participants achieving a heart rate of 140 bpm or higher showed that changes in submaximal heart rate in the group cycling with moderate to high intensity (ie, heart rate > or =140 bpm) were clearly related to changes in VO(2)peak and peak power output. CONCLUSIONS For the monitoring of training progress in daily clinical practice, changes in heart rate at a fixed submaximal workload that requires a heart rate greater than 140 bpm may serve as an alternative to an exhaustive exercise test.