Association between heart rate variability and training response in sedentary middle-aged men

Area of Science:

• Exercise Physiology
• Cardiovascular Health
• Sports Science

Background:

• Sedentary lifestyles contribute to decreased cardiovascular fitness.
• Heart rate variability (HRV) and peak oxygen consumption (VO2peak) are key indicators of cardiovascular health.
• The relationship between HRV and exercise-induced improvements in VO2peak requires further investigation.

Purpose of the Study:

• To investigate the effects of a moderate-intensity exercise program on HRV and VO2peak in sedentary middle-aged men.
• To explore whether baseline HRV influences the response of VO2peak to exercise training.

Main Methods:

• A 24-session moderate-intensity exercise training program was administered to a group of sedentary middle-aged men (n=19).
• A control group (n=15) did not participate in the training program.
• HRV and absolute and relative VO2peak were measured before and after the intervention period.

Main Results:

• The training group showed significant increases in absolute and relative VO2peak (12% and 11%, respectively) and a reduction in resting heart rate.
• HRV did not significantly change in the training group.
• Subgroup analysis revealed that individuals with higher baseline HRV experienced significantly greater improvements in VO2peak compared to those with lower baseline HRV.

Conclusions:

• A short-term aerobic training program does not alter HRV in sedentary middle-aged men.
• Individual differences in baseline HRV may predict the magnitude of VO2peak improvement in response to aerobic training.
• Higher baseline HRV is associated with a more favorable response to exercise training in terms of cardiorespiratory fitness.