T10 Test as an Alternative Method to Assess Critical Speed and its Potential Application to Runners

Exercise intensity is usually prescribed based on a metabolic marker, such as maximum oxygen uptake or maximal lactate steady state. Those markers, however, face some difficulties regarding their practical applicability to the general population. The critical speed emerges as an alternative parameter to determine aerobic exercise intensities through maximal tests using ergometers or field tests, demanding few resources. We evaluated the fidelity of test to predict critical speed and if this parameter could be used to prescribe intensity in aerobic exercise. One hundred recreational runners performed the T10 test and a conventional critical speed test to define running speeds. Out of them, 44 runners proceed continuous and interval races. The critical speed assessed from T10 test was then compared to critical speed measured by three maximal runs in the track field (1200 m, 2400 m, and 3600 m). We found a strong correlation ( r = 0.91) and did not find statistical differences ( t = 1.8, P = 0.90) between critical speed assessed by T10 (3.89 ± 0.49 m/s) and field-test (3.85 ± 0.51 m/s). T10 is also better associated with running and interval running speeds than metabolic markers. T10 test can be used as a valid alternative method to assess critical speed and to prescribe runs.