Efficacy of a Regression Method to Confirm VO2max in Middle-Aged and Older Adults: A Pilot Study

Authors

Jeremy B. Ducharme, University of New MexicoFollow
Zachary J. McKenna, University of New MexicoFollow
Christine M. Mermier, University of New MexicoFollow
Ann L. Gibson FACSM, University of New MexicoFollow

Abstract

Verification testing following a maximal graded exercise test (GXT) has been shown to be effective at indicating whether VO₂max was attained for middle-aged and older adults but performing two maximal efforts in a single day may not be practical or possible for certain individuals. PURPOSE: To evaluate the efficacy of a regression method for identifying a VO₂ plateau in order to confirm the attainment of VO₂max. METHODS: Twenty-one recreationally active (VO₂max: 21.8-50.3 ml/kg/min) middle-aged and older (46-76 yrs.) men (n=11) and women (n=10) completed an individualized ramp GXT on the cycle ergometer, and one hour later, a verification protocol at 105% of their maximal work rate (WR) achieved during the GXT. Verification criterion was met if the difference between the highest VO₂ during the verification was ≤2% greater than the VO₂max achieved during the GXT. VO₂ plateau was identified by least-squares regression analysis of the 4 minutes immediately prior to the last 2 minutes of the VO₂-WR curve. Modelled VO₂max was extrapolated using the VO₂-WR regression equation and the maximum WR achieved during the GXT. If the difference between modelled and actual VO₂max was >50% of the slope for the linear portion of the VO₂-WR relationship relative to the assigned protocol, then a plateau was observed. McNemar’s test of marginal homogeneity was used to detect differences in the proportion of paired data of individuals’ attainment of VO₂max criteria. RESULTS: 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 (Χ²(1)=0, p=.999). CONCLUSION: The regression method used in this study may be an effective strategy for determining VO₂ plateau and confirming that VO₂max was attained during a GXT 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.

Recommended Citation

Ducharme, Jeremy B.; McKenna, Zachary J.; Mermier, Christine M.; and Gibson, Ann L. FACSM (2021) "Efficacy of a Regression Method to Confirm VO2max in Middle-Aged and Older Adults: A Pilot Study," International Journal of Exercise Science: Conference Proceedings: Vol. 14: Iss. 1, Article 9.
Available at: https://digitalcommons.wku.edu/ijesab/vol14/iss1/9