Yu TY, Hong WJ, Jin SM, et al. - This study was undertaken to investigate the longitudinal association of delayed heart rate recovery (HRR) following a graded exercise treadmill test (GTX) with incident metabolic syndrome (MetS). Researchers performed a retrospective longitudinal cohort study of participants without MetS, diabetes, or cardiovascular diseases. They computed HRR as peak heart rate minus resting heart rate after a one-minute rest, a two-minute rest, and a three-minute rest. The relationship between HRR and development of MetS was investigated by performing Multivariate Cox proportional hazards analysis. The study enrolled a total of 676 (31.2%) incident cases of MetS who were identified during the follow-up period (9,683 person-years). The results reveal the phase of HRR, especially HRR3, might be more sensitive at predicting the risk of MetS.