Reliability of Time Spent Near V̇ o2 max During 2 Cycling Interval Training Sessions: The Effect of V̇ o2 max...

Raimundo, JAG, Tramontin, AF, Martins, EC, Borszcz, FK, Turnes, T, de Aguiar, RA, and Caputo, F. Reliability of time spent near V̇ o2 max during 2 cycling interval training sessions: the effect of V̇ o2 max criteria. J Strength Cond Res 39(9): e1067-e1074, 2025-This study aimed to determine the reliability of the time spent near V̇ o2 max (tV̇ o2 max) during 2 work-matched cycling interval trainings and to compare tV̇ o2 max reliability using different V̇ o2 max criteria. Fifteen healthy males participated in this cross-sectional and crossover study. The participants performed on different days, an incremental ramp test followed by a V̇ o2 max verification test, and a test-retest model to analyze tV̇ o2 max during 2 distinct work-matched interval training sessions. The interval training protocols comprised 5 × 2-minute efforts with 1-minute recovery (HIIT 2min:1min ) or 10 × 1-minute efforts with 30-second recovery (HIIT 1min:30s ) at 85% of the incremental peak power output, both followed by a V̇o 2 max verification test. Times sustained above 90 and 95% (t95V̇ o2 max) of V̇ o2 max were analyzed and were compared based on 3 different criteria: (a) V̇ o2 max from incremental and verification test (V̇ o2 max INC-VER ); (b) V̇ o2 max from the verification test on the training day (V̇ o2 max DAY ); and (c) mean V̇ o2 max from V̇ o2 max INC-VER and V̇ o2 max DAY . There were no significant differences in test-retest tV̇ o2 max; the only exception was t95V̇ o2 max during HIIT 1min:30s assessed by V̇ o2 max INC-VER . The typical error of measurement and coefficient of variation ranged from 28 to 61 seconds and 19%-35% for HIIT 2min:1min , and from 21 to 66 seconds and 36%-72% for HIIT 1min:30s . V̇ o2 max INC-VER reduced tV̇ o2 max coefficient of variation compared with V̇ o2 max DAY for HIIT 2min:1min , but not for HIIT 1min:30s . Despite similar test-retest, tV̇ o2 max exhibited low reliability, with no improvement when a V̇ o2 max verification test was included on the training day.