Table 1.

Description of variables

Variable	Description
Resting heart rate	Heart rate in number of beats per minute while sitting quietly
HRR60	Immediate heart rate recovery Calculated as: maximal heart rate—heart rate at 1 min after exercise
HRR180	Long-term heart rate recovery Calculated as: maximal heart rate—heart rate at 3 min after exercise
Resting RSA	Resting respiratory sinus arrhythmia Calculated via peak valley method while sitting quietly by averaging RSA in all breaths during 6 min of quiet sitting
RSA60	Immediate vagal rebound Respiratory sinus arrhythmia, an average of the RSA across all breaths in the first minute after exercise
RSA300	Long-term vagal rebound Respiratory sinus arrhythmia, an average of the RSA across all breaths in minute 2–5 after exercise