Power-cadence relationship in endurance cycling

Area of Science:

• Sports Science
• Exercise Physiology
• Cycling Biomechanics

Background:

• The power-cadence relationship is crucial for determining maximal power output (Pmax) and optimal cadence (Copt) in cycling.
• Existing research primarily focuses on sprint cycling, often reporting a quadratic relationship passing through the origin.

Purpose of the Study:

• To evaluate a quadratic regression model for assessing Pmax and Copt in endurance cycling.
• To test the hypotheses that a quadratic fit accurately describes the power-cadence relationship and reliably estimates Pmax and Copt within typical cycling cadence ranges.

Main Methods:

• A theoretical model simulated the power-cadence relationship.
• An experimental approach involved eight cyclists performing incremental tests at various cadences (70-110 rpm) at fixed blood lactate concentrations (3-4 mmol/L).
• Quadratic regression analysis was applied to the collected power-cadence data.

Main Results:

• The theoretical model showed negligible bias (1.0 W for Pmax, 0.6 rpm for Copt) when fitted with a quadratic regression.
• Experimental data demonstrated excellent fit to quadratic regressions (R² = 0.94–0.96).
• The 95% confidence intervals for individual Pmax and Copt assessments were ±4.4 W and ±2.9 rpm, respectively.

Conclusions:

• The proposed quadratic regression method effectively estimates the power-cadence relationship, Pmax, and Copt in endurance cycling.
• This method provides a reliable and accurate tool for assessing key performance indicators for endurance cyclists.
• The findings support the use of this model for practical applications in cycling performance analysis.