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A test used by cyclists to measure their performance or fitness level.

Example usage: The cyclist completed a critical-power-test to measure his peak performance.

Most used in: Cycling circles, particularly in Europe.

Most used by: Professional cyclists and those training for competitive events.

Popularity: 8/10

Comedy Value: 2/10

Also see: Functional Threshold Power Test, FTP Test, Ramp Test, Power Profile Test,


What is a Critical Power Test?

A critical power test is a type of cycling test used to assess an individual’s performance and fitness level. It is a time trial of a set duration, typically between five and thirty minutes, during which cyclists must maintain a constant power output. The goal of the test is to determine the cyclist’s maximum sustainable power output (or critical power).

Critical power tests measure how efficiently a cyclist can sustain their power output over an extended period of time, and are considered to be a reliable measure of aerobic fitness. The test results are used to calculate the cyclist’s critical power, which is the highest power output that they can sustain for a given duration. This value can then be used to determine an individual’s training zones, and to help set goals for future performance.

Critical power tests are becoming increasingly popular among competitive cyclists, as they provide an objective measure of the cyclist’s current fitness level and potential for improvement. The test is also valuable for coaches, as it provides a reliable benchmark for athletes’ progress. According to a study in the International Journal of Sports Physiology and Performance, the average critical power for elite male cyclists was found to be 5.45 watts per kilogram of body weight and 4.98 watts per kilogram of body weight for elite female cyclists.

The Origin of the Term 'Critical Power Test' in Cycling

The term 'Critical Power Test' was first used in the context of cycling in the early 1980s in the United Kingdom. The term was coined by Professor David Swain of Birmingham University, who was researching the effects of fatigue during cycling performance.

Swain and his team sought to develop a test protocol that could measure an athlete’s anaerobic threshold, or the point at which the body is no longer able to sustain a steady effort. The test was designed to determine the maximum sustainable power output of a cyclist, and the results of the test could be used to develop individualized training plans.

The Critical Power Test was first used in a scientific study in 1983, and it quickly gained popularity among cycling coaches and athletes. The test is still used today as one of the most reliable ways to measure an athlete’s anaerobic threshold and to develop individualized training plans.

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