Critical Swim Speed Test (CSS)

The Critical Swim Speed is defined as the theoretical swimming speed that can be maintained continuously without exhaustion. This test can be used by coaches and swimmers as a measure of aerobic capacity and also to determine swimming training intensities. A CSS test was described by Wakayoshi et al. (1992) using swims over 4 distances (50, 100, 200, 400m), and the CSS determine as the slope of the regression line relating distance and time. This was later simplified to a two swim test (50m and 400m) by Ginn (1993) and using a simple formula to determine CSS. Below is the test as described by Ginn.

CSS (m/sec) = (D2 - D1) ÷ (T2 - T1)

Ginn found that the CSS for a swimmer was about 80 to 85% of maximum 100m swim speed and 90 to 95% of their 400m swim speed.


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