The exercise intensity at maximal oxygen uptake (i⩒O2max): methodological issues and repeatability
Date
2016Author
Merry, Kevin L.
Howatson, Glyn
Glaister, Mark
Van Someren, Ken
Metadata
Show full item recordAbstract
The minimum exercise intensity that elicits V̇O2max (iV̇O2max) is an important variable associated with endurance exercise
performance. iV̇O2max is usually determined during a maximal incremental exercise test; however, the magnitude and
duration of the increments used influence the iV̇O2max value produced by a given test. The aims of this study were
twofold. The first was to investigate whether the iV̇O2max value produced by a single cycle ergometer test (iV̇O2max(S)) was
repeatable. The second was to determine if iV̇O2max(S) represents the minimum intensity at which V̇O2max is elicited when
compared to a refined iV̇O2max value (iV̇O2max(R)) derived from repeated tests. Seventeen male cyclists (age 33.9 ± 7.7
years, body mass 80.9 ± 10.2 kg, height 1.82 ± 0.05 m; VO2max 4.27 ± 0.62 L min−1) performed four maximal incremental
tests for the determination of iV̇O2max(S) and iV̇O2max(R) (3 min stages; 20 W increments). Trials 1 and 2 were identical
and used for assessing the repeatability of iV̇O2max(S), trials 3 and 4 began at different intensities and were used to
determine iV̇O2max(R). iV̇
O2max(S) showed good test–retest repeatability for iV̇O2max (CV = 4.1%; ICC = 0.93), VO2max
(CV = 6.3%; ICC = 0.88) and test duration (CV = 6.7%; ICC = 0.89). There was no significant difference between
iV̇O2max(S) and iV̇O2max(R) (303 ± 40W vs. 301 ± 42 W) (P < .05). The present results suggest that iV̇O2max determined
directly during a maximal incremental test is repeatable and provides a very good estimate of the minimum exercise
intensity that elicits V̇O2max.