The effect of intensity and duration of verification stages on the efficacy of VO2max testing

Authors

Andrew Foster, James Madison UniversityFollow

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.

Date of Graduation

5-12-2022

Semester of Graduation

Spring

Degree Name

Master of Science (MS)

Department

Department of Kinesiology

Second Advisor

Nicholas D. Luden

Third Advisor

Stephanie Kurti

Abstract

Purpose: To determine if changing the length of the recovery stage influences the effectiveness, or ability to confirm maximal oxygen consumption (VO_2max), of the verification phase and if the initial intensity of the stage has an impact on its effectiveness. Methods: 27 subjects (20 males and 7 females) performed four separate VO_2max tests separated by at least 48 hours. For each initial graded exercise test, starting speed was 3.0 mph and increased by 0.5 mph every minute until 6.0 mph was reached. After this point, elevation was increased by 3.0% every minute until volitional exhaustion. VO₂ was continuously tracked using a Parvomedics metabolic measurement system. Heart rate and RPE was gathered at the end of every minute. The highest 30s average achieved during the graded exercise test was defined as VO_2max for the incremental test (iVO_2max). Four different verification stages followed and included combinations of short (5-min) and long (15-min) rest periods, and submaximal (one stage beneath maximal workload) and supramaximal (one stage above maximal workload) intensities. Results: There were no significant difference between iVO_2max and verification VO_2max (vVO_2max) across all protocols. RER was lower (P < 0.05) during the verification stage compared to the graded exercise test for the long/submaximal and short/supramaximal protocol. HR_max was similar between GXT and short/submaximal verification stage, whereas the other three verification protocols elicited lower HR_max values. Average verification RPE was significantly higher than average GXT RPE for the long/supramaximal protocol. Though VO_2max was not different between GXT and verification stage, the short/submaximal protocol resulted in 81.5% of subjects with vVO_2max the same or higher than iVO_2max. Conclusion: Based on fewer tests with vVO2max < iVO2max, it may be preferable to use shorter rest periods with submaximal initial intensity for verification stages.