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Training tools

Useful tools to establish power and heart rate performance metrics.

Critical power & W' calculator

Critical Power (CP) in cycling refers to the highest sustainable power output that a cyclist can maintain for a prolonged period without fatigue setting in. It's often determined through testing protocols and represents a key physiological parameter for endurance athletes. CP serves as a reference point for setting training zones, pacing strategies, and race tactics, allowing cyclists to optimize their efforts for maximum performance and efficiency. By training at or near CP, athletes can improve their aerobic capacity, endurance, and lactate threshold, leading to enhanced race performance and overall cycling prowess.

Work Prime (W') represents the finite energy reserve available for high-intensity efforts during cycling, crucial for strategic pacing and optimizing performance.

Enter the power average for three maximal efforts of between 3 minutes and 20 minutes. It's recommended to use 3, 5 and 12 minutes.

Critical Power (w)
eFTP (w)
W' (kj)
Accuracy of above 97% suggests the results are valid.

Critical power predictor

Predicted power (W)
Predicted duration (Seconds)

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