Post‐Exercise Heart Rate Recovery is Impaired in Anabolic Steroids Users

Abstract

Purpose We hypothesized that heart rate recovery (HRR) would be lower in anabolic androgenic steroids users (AASU) compared with anabolic androgenic steroids nonusers (AASNU). Methods Eight AASU and 7 AASNU participated in the study. Anabolic steroid was tested by urine (chromatography-mass spectrometry). Cardiopulmonary exercise was performed on treadmill ramp protocol. Heart rate was evaluated by a 12 leads EKG. Muscle sympathetic nerve activity (MSNA) was measured by microneurography. Results Peak oxygen consumption was lower in AASU compared with AASNU (45±2.27 vs. 52±1.85 ml/kg/min, P=.04). Peak HR was not different between groups (189±3 vs. 184±2 bpm, P=.28). There were no difference in peak respiratory exchange ratio between groups (1.26±.05 vs. 1.26±.03, P=.96). The HRR at first and second minute of recovery was lower in AASU than AASNU (18±2 vs. 26±1 bpm, P=.003; 34±4 vs. 43±1 bpm, P=.04, respectively). MSNA was higher in AASU than AASNU (29±3 vs. 20±1 bursts/min, P=.01). Further analysis showed an inverse correlation between MSNA and HRR (r=.64, P=.02). Conclusion The impairment in HRR during the post-exercise period and the increased MSNA are consistent with autonomic dysfunction in AASU.