Comparing Heart Rate Recovery After Aerobic vs. Anaerobic Exercise

Abstract

Background: Heart rate recovery (HRR) is a key physiological marker of autonomic nervous system function and cardiovascular fitness. It reflects the ability of the heart to return to baseline after exercise, influenced by parasympathetic reactivation and sympathetic withdrawal. While both aerobic (e.g., running, cycling) and anaerobic (e.g., sprinting, weightlifting) exercises influence HRR, their comparative effects remain an area of interest. This study aims to compare HRR after aerobic and anaerobic exercise, analyzing differences in autonomic modulation and cardiovascular recovery.

Methods: A total of 210 healthy adults (mean age: 28.5 ± 5.7 years) were recruited and divided into two exercise groups: Aerobic Exercise Group (n = 105) and Anaerobic Exercise Group (n = 105). Participants performed a standardized 30-minute treadmill running protocol (aerobic) or high-intensity sprinting and resistance training (anaerobic). Heart rate (HR) was monitored continuously using ECG, and HRR was assessed at 1 minute (HRR1), 2 minutes (HRR2), and 5 minutes (HRR5) post-exercise.

Results: HRR was significantly faster in the aerobic exercise group, with greater parasympathetic reactivation observed at HRR1 (p < 0.001) and HRR2 (p = 0.003). The anaerobic group exhibited a slower decline in HR, with significantly higher HR at HRR1 and HRR2 compared to the aerobic group. At HRR5, no significant differences were observed between groups (p = 0.081).

Conclusion: Aerobic exercise facilitates faster heart rate recovery compared to anaerobic exercise, suggesting superior parasympathetic reactivation and autonomic function. While anaerobic exercise leads to delayed HRR due to prolonged sympathetic activation, both exercise modalities contribute to cardiovascular fitness in distinct ways. Future studies should explore long-term HRR adaptations in athletes and clinical populations.

Keywords: Heart rate recovery, aerobic exercise, anaerobic exercise, autonomic nervous system, cardiovascular fitness