A comparison between the performance of active duty Air Force personnel on the United States Air Force submaximal bicycle ergometry aerobic fitness test and the Air National Guard submaximal step test

The United States Air Force (USAF) uses a submaximal cycle ergometry (SCE) test to assess aerobic fitness in over 385,000 members. The Air National Guard (ANG) uses a submaximal step test (ST) to assess aerobic fitness in over 175,000 members. Submaximal cycle and step tests have been purported to yield similar results, although no research has compared USAF SCE and the ANG ST. The purpose of this study is to determine if the ANG ST is a viable alternative to USAF SCE in terms of assessing aerobic fitness.;The study population was comprised of 74 (42 males, 19--48 years old and 32 females, 19--41 years old) active duty Air Force members performing their annual SCE. Consecutive eligible subjects were recruited from active duty Air Force personnel performing their annual SCE test. The order of testing was conducted as follows: (1) USAF SCE, (2) ANG ST, and the (3) Bruce maximal treadmill test. The Pearson (r) was used to determine association between the test methods. A "Z" test statistic was calculated from the Pearson "r" for hypothesis testing. A 95% confidence interval was calculated to determine clinical significance.;The strength of the correlation between USAF SCE and the ANG ST in males was r = 0.98 and r = 0.96 in females. The mean difference between the two tests in males was 1.64 ml/kg/min (95% CI 1.02, 2.27) and in females was 1.00 ml/kg/min (95% CI 0.52, 1.48). The strength of the correlation between USAF SCE and the Bruce maximal treadmill test in males was r = 0.98 and r = 0.87 in females. The strength of the correlation between ANG ST and the Bruce maximal treadmill test in males was r = 0.97 and r = 0.93 in females.;Clinically, both tests can be used interchangeably. However, the cost of the USAF SCE test in terms of time, personnel, and resource requirements makes it the prohibitive choice. Therefore, the ANG ST is the best choice of the two for assessing aerobic fitness in active duty Air Force members at their home base or while deployed.