Evaluation of autonomic function underlying slow postexercise heart rate recovery.

Unlabelled: The reduction in heart rate (HR) during the first minute of recovery immediately after a graded maximal exercise stress test (GXT) has recently been found to be a powerful and independent predictor of cardiovascular and all-cause mortality. Reduced vagal activity has been postulated as the cause, but this has not been proven in a population with slow HR recovery (HRR).

Purpose: To investigate autonomic contributions to HRR using time-frequency analysis in a group of individuals demonstrating slow HRR.