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Calculating Heart Rate Variability from ECG Data from Youth with Cerebral Palsy During Active Video Game Sessions

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Altitude, heart rate variability and aerobic capacities.

L Schmitt¹, J-P Fouillot, G P Millet

¹Recherche et Entraînement, Centre National de Ski Nordique, Les Rousses, France. laurent.schmitt@jeunesse-sports.gouv.fr

International Journal of Sports Medicine

|August 10, 2007

Summary

Heart rate variability (HRV) changes were linked to aerobic capacity improvements in skiers using the living high-training low method. HRV monitoring can help track altitude training adaptations.

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Area of Science:

Sports Science
Altitude Training Physiology
Cardiovascular Regulation

Background:

Living high-training low (Hi-Lo) is a common altitude training strategy.
Understanding physiological adaptations to Hi-Lo is crucial for athlete performance.
Heart rate variability (HRV) is a sensitive indicator of autonomic nervous system function and training status.

Purpose of the Study:

To investigate the relationship between aerobic capacity changes and HRV alterations in elite Nordic skiers during a Hi-Lo protocol.
To determine if HRV can serve as a monitoring tool for altitude training adaptations.

Main Methods:

Eleven Nordic skiers underwent an 18-day Hi-Lo protocol, with two groups: continuous low-level hypoxia (LL) and intermittent high-level hypoxia (HL).
Aerobic capacity (VO2max, peak power output, VO2 and power at respiratory compensation point) and HRV were measured before, during, and after the intervention.
Statistical analyses correlated changes in HRV parameters (TP, HF, LF) with changes in aerobic capacity metrics.

Main Results:

No significant improvements in VO2max or peak power output were observed in either group.
Significant increases in VO2 and power at the respiratory compensation point (VO2RCP, PRCP) were found only in the HL group.
The LL group showed significant increases in resting heart rate (HR) and decreases in total spectral power (TP) and high-frequency activity (HF) in the standing position.
Pooled analysis revealed significant correlations between supine HRV parameters (HF, LF, TP) and changes in VO2RCP and PRCP.

Conclusions:

The study confirms a relationship between HRV changes and aerobic capacity adaptations in athletes undergoing altitude training.
HRV parameters, particularly when measured in the supine position, show potential as a non-invasive tool for monitoring the effectiveness of Hi-Lo altitude training protocols.
These findings underscore the utility of HRV for optimizing training load and adaptation assessment in endurance athletes.