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Photoplethysmography Detection of Overreaching
Nicolas Bourdillon1, Masih Nilchian2, Grégoire P Millet1
1ISSUL, Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, SWITZERLAND.
Medicine and Science in Sports and Exercise
|November 9, 2018
Summary
Photoplethysmography (PPG) effectively distinguishes between functional overreaching (FOR) and acutely fatigued (AF) endurance athletes. This method allows for timely training adjustments to prevent nonfunctional overreaching and optimize performance.
Area of Science:
- Sports Science
- Physiology
- Biomedical Engineering
Background:
- Detecting overreaching in endurance athletes is crucial for training program adjustments.
- Functional overreaching (FOR) and nonfunctional overreaching require different management strategies.
- Photoplethysmography (PPG) is a non-invasive technique that measures blood volume changes.
Purpose of the Study:
- To assess PPG's ability to differentiate between FOR and acutely fatigued (AF) athletes.
- To determine if specific PPG characteristics can distinguish FOR from AF.
- To evaluate PPG as a tool for timely detection of overreaching in athletes.
Main Methods:
- Fifteen athletes underwent a 2-week baseline, 3-week overload, and 2-week recovery training protocol.
- Performance was assessed using a 3000m time-trial to identify FOR and AF.
- Overnight PPG data, including amplitude and time variations, were collected using a wearable sensor.
Main Results:
- Performance decreased in FOR athletes but improved in AF athletes post-overload.
- Diastolic time was longer in AF, while systolic slope was smaller in AF compared to FOR.
- Variances in PPG signals (amplitudes, slopes, pulse areas) were lower in AF than in FOR during overload.
Conclusions:
- PPG is an effective tool for detecting overreaching by distinguishing FOR and AF athletes.
- The fast-responding nature of PPG allows for immediate training adjustments.
- Utilizing PPG can help prevent nonfunctional overreaching and guide training modifications.
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