Reliability and Validity of the T-Test as a Measure of Agility, Leg Power, and Leg Speed in College-Aged Men and Women

The reliability and validity of the T-test as a measure of leg power, leg speed, and agility were examined. A total of 304 college-aged men (n 5 152) and women (n 5 152), selected from varying levels of sport participation, performed 4 tests of sport skill ability: (a) 40-yd dash (leg speed), (b) countermovement vertical jump (leg power), (c) hexagon test (agility), and (d) T-test. For both men and women, significant differences (p , 0.05) in mean scores were found among groups for the T-test. The intraclass reliability of the T-test was 0.98 across 3 trials. For men, the Pearson product moment correlations between the T-test and the 40-yd dash, vertical jump, and hexagon test were r 5 0.53, r 52 0.49, and r 5 0.42, respectively (p , 0.05). For women, the corresponding correlations were r 5 0.73, r 52 0.55, and r 5 0.48 (p , 0.05). Regression analyses showed that for men 48% of the variability and for women 62% of the variability of the T-test scores can be predicted from measures of leg power, leg speed, and agility (p , 0.05). Computing partial correlations assessed the criterion validity of the T-test as a measure of agility, leg power, and leg speed. The T-test appears to be highly reliable and measures a combination of components, including leg speed, leg power, and agility, and may be used to differentiate between those of low and high levels of sports participation.