Can the Six-Minute Walk Test Be Used to Individualize Physical Activity Intensity in Patients with Breast Cancer?

Background: Adapted physical activity (APA) aids breast cancer patients. It is necessary to use an adapted target heart rate (HR) when prescribing exercise intensity. Methods: In total, 138 patients previously included in two published randomized clinical trials underwent the CPET and 6MWT before and after adjuvant therapy. Of these patients, 85 had performed APA, and 53 had received only the usual therapy. HRs were recorded during the two tests. Results: Before starting chemotherapy, good agreement (intraclass correlation (ICC) 0.69; confidence interval at 95% IC0.95 (0.591–0.769); p < 0.001) and a moderate correlation were evident between the 6MWT-HR and ventilatory threshold HR of the CPET (r = 0.70; p < 0.001). Good agreement and a high positive correlation were noted only in the group who engaged in APA (ICC 0.77; IC0.95 (0.659–0.848); p < 0.001; r = 0.8; p < 0.01); moderate agreement and a moderate positive correlation were apparent in the control group (ICC 0.57; IC0.95 (0.329–0.74); p < 0.001; r = 0.6; p < 0.01). The correlations were independent of age and body mass index. Conclusions: The 6MWT-HR can be used to prescribe exercise intensity for breast cancer patients both before and after specific treatment with concomitant APA.