The Reliability of Cooper ́s Test in Subjects Between 28-60 Years of Age

Abstract: Background: Maximal oxygen uptake (VO2max) is a determinant of an individual’s ability to handle oxygen during maximal exercise. To measure VO2max expensive equipment and expertise personnel are required. To make the process of measuring VO2max easier, several submaximal and maximal tests have been created in which an estimation of VO2max could be made. Cooper’s 12-minute run (12MR) was created in 1968 and was tested on 115 military men with a mean age of 22 years. Since then the 12MR test has been re- tested and validated towards maximal treadmill tests on several occasions. When an age of 30 years is reached, VO2max starts to decline with 9-10 percent per decade but can be halted by different forms of exercise. With exercise of moderate to high intensity the decline can be halted by almost 50 percent. Objective: To investigate the reliability of estimated VO2max in a test retest scenario of Cooper ́s 12MR on a mixed healthy population between the ages of 28-60. Method: Nine women and five men, healthy subjects with a mean age of 43 ± 8 participated in the present study. A test retest of Cooper ́s 12MR took place with a minimum of seven days between tests. The subjects had to run as many laps as possible on the track during a 12-minute period. Finished laps were then counted and the fraction of the last lap was measured with a measuring wheel and then added to the total distance. To estimate the subjects’ VO2max Cooper ́s table was used. Results: The single measure Intraclass correlation (ICC) that was found, between the estimated VO2max made from the initial test to the retest on Cooper ́s 12MR, was 0.979. ICC showed a small error variance correlation between the tests and was close to the optimal correlation of 1.0. Conclusion: A standardized protocol for performing Cooper ́s 12MR showed good repeatability for estimating VO2max in two separate tests for a mixed population between 28 to 60 years of age.