Can linear regression confirm VO2max was attained in middle-aged and older adults?

Abstract

Evaluate the efficacy of a regression method for identifying a VO2 plateau to confirm the attainment of VO2max compared to a verification trial in middle-aged and older adults. Eleven men and ten women (age 61.0 ± 8.1, VO2max 21.8-50.3ml/kg/min, n = 21) completed an individualized ramp graded exercise test (GXT) on the cycle ergometer, and one hour later, a verification trial at 105% of their maximal work rate (WR) achieved during the GXT. A plateau in VO2 was used to confirm VO2max was attained. VO2 plateau was identified using the difference between the highest VO2 between the two trials and a linear regression analysis of the VO2-WR relationship during the GXT. McNemar's test of marginal homogeneity was used to detect differences in the proportion of paired data of individuals' attainment of VO2max criteria. Of the 21 participants, 15 (71.4%) met the verification criterion while 6 (28.6%) did not, compared to the regression method where 16 (76.2%) achieved the regression criterion while 5 (23.8%) did not. McNemar's test revealed no significant difference between participants' ability to achieve the regression and verification criteria (p = 0.999). The regression method is an effective strategy for confirming VO2max was attained with middle-aged and older adults on a cycle ergometer. This time-efficient regression method is comparable with the verification criterion but does not require a second maximal test, which may be advantageous for those where the verification trial may not be practical.