Heart Rate Recovery (HRR) Is Not a Singular Predictor for Physical Fitness

Background: For optimal recommendations in cardiovascular training for the general population, knowing the essential parameters for physical fitness is required. Heart rate recovery (HRR) is an easy-to-measure parameter and is discussed to derive the physical fitness of an individual subject. This study evaluates HRR as a potential physical fitness parameter for public health programs, as it is measured in every ergometry. Methods: In this retrospective cross-sectional study, we analyzed HRR regarding physical fitness (W/kg (IAT: individual anaerobic threshold)). In total, we analyzed 1234 performance protocols in cycle ergometry. Significance tests (p < 0.001) and multiple linear regression were performed. Results: The analysis of HRR and weight-related performance showed a significant correlation with a moderate coefficient of determination (R2 = 0.250). The coefficient of determination increases from very weak correlation levels at 1 min post-workout towards weak to moderate levels of correlation at 5 min post-workout. Conclusions: In this study HRR and the weight-related performance at the IAT showed a significant correlation with a mean strength. Thus, a prediction or conclusion on physical performance based singularly on HRR decrease is not recommended. However, in preventive medicine, HRR should be measured and observed on a long-term basis, for analysis of vagal activity and to draw to inferences of mortality.