Long-term exercise training improves autonomic nervous system profile in professional runners

Area of Science:

• Exercise Physiology
• Autonomic Nervous System Function
• Sports Science

Background:

• Endurance training intensity influences autonomic nervous system (ANS) activity, with moderate loads increasing parasympathetic tone and extreme loads potentially elevating sympathetic tone.
• Regional class athletes typically engage in less intensive training compared to elite or champion athletes.

Purpose of the Study:

• To investigate the impact of a long-term training cycle on the autonomic nervous system activity of regional class runners.
• To assess changes in cardiovascular autonomic regulation during preparation for competitions.

Main Methods:

• Twenty-four regional class runners underwent assessment of resting heart rate and autonomic tone.
• Non-invasive measurements of systolic arterial pressure and heart rate were recorded for spectral analysis.
• Arterial baroreflex sensitivity (BRS_WBA) and heart rate variability (HRV) indices (SDNN, pNN50, RMSSD, TP, LF, HF) were calculated.

Main Results:

• Significant increases were observed in BRS_WBA, SDNN, pNN50, TP, and LF during the competition period compared to the preparatory phase.
• A trend towards increased RMSSD was noted, although not statistically significant.
• No significant differences were found in other HRV parameters.

Conclusions:

• Long-term intensive training in regional class runners leads to a shift in autonomic profile, favoring parasympathetic nervous system dominance.
• This autonomic adaptation may contribute to improved cardiovascular health and performance.
• The findings support encouraging participation in high-intensity endurance sports for young, healthy individuals.