Validation of a novel intermittent w' model for cycling using field data

Area of Science:

• Exercise Physiology
• Sports Science
• Performance Analytics

Background:

• The critical-power (CP) model has been adapted to calculate work capacity remaining balance (W'bal) during intermittent exercise.
• This W'bal model is increasingly used by amateur and elite athletes for performance monitoring.

Purpose of the Study:

• To validate the W'bal model's effectiveness in real-world training and competition settings.
• To assess the W'bal model's ability to predict premature exhaustion in athletes.

Main Methods:

• Collected data from bicycle power meters of 8 trained triathletes.
• Calculated W'bal and compared values between instances of exhaustion and successful task completion.
• Utilized receiver-operator characteristic (ROC) curve analysis to evaluate predictive accuracy.

Main Results:

• Significant differences in calculated W'bal were observed between exhausted and non-exhausted conditions (P < .0001).
• Mean W'bal at exhaustion was 0.5 ± 1.3 kJ, while minimum W'bal in non-exhausted states was 3.6 ± 2.0 kJ.
• ROC analysis showed the W'bal model is a useful predictor of exhaustion risk (area under curve = .914, P < .0001).

Conclusions:

• The W'bal model demonstrates validity for field-based assessment of athlete fatigue.
• This model offers a valuable tool for monitoring fatigue status during training and racing.
• The W'bal model can help athletes identify critical points of potential exhaustion.