Comparison of the YMCA and a Custom Submaximal Exercise Test for Determining (V) over dotO2max

The maximal oxygen uptake ((V) over dotO(2max)) is deemed the highest predictor for all-cause mortality, and therefore, an ability to assess (V) over dotO(2max) is important. The YMCA submaximal test is one of the most widely used tests to estimate (V) over dotO(2max); however, it has questionable validity. Purpose: We validated a customized submaximal test that accounts for the nonlinear rise in (V) over dotO(2) relative to power output and compared its accuracy against the YMCA protocol. Methods: Fifty-six men and women performed a graded exercise test with a subsequent exhaustive, square wave bout for the verification of "true" (V) over dotO(2max). In counterbalanced order, subjects then completed the YMCA test and our new Mankato submaximal exercise test (MSET). The MSET consisted of a 3-min stage estimated at 35% (V) over dotO(2max) and a second 3-min stage estimated at either 65% or 70% (V) over dotO(2max), where (V) over dotO(2max) was estimated with a regression equation using sex, body mass index, age, and self-reported PA-R. Results: (V) over dotO(2) values from the graded exercise test and square wave verification bout did not differ with the highest value used to identify "true" (V) over dotO(2max) (45.1 +/- 8.89 mL.kg(-1).min(-1)). The MSET (43.6 +/- 8.6 mL.kg(-1).min(-1)) did not differ from "true" (V) over dotO(2max), whereas the YMCA test (41.1 +/- 9.6 mL.kg(-1).min(-1)) yielded an underestimation (P = 0.002). The MSET was moderately correlated with "true" (V) over dotO(2max) (ICC = 0.73, CV of 11.3%). The YMCA test was poorly correlated with "true" (V) over dotO(2max) (ICC = 0.29, CV of 15.1%). Conclusions: To our knowledge, this is the first study to examine submaximal exercise protocols versus a verified (V) over dotO(2max) protocol. The MSET yielded better estimates of (V) over dotO(2max) because of the protocol including a stage exceeding gas exchange threshold.