Application of V[Combining Dot Above]O2 to the Critical Power Model to Derive the Critical V[Combining Dot Above]O2.

ABSTRACT Succi, PJ, Dinyer, TK, Byrd, MT, Voskuil, CC, and Bergstrom, HC. Application of V[Combining Dot Above]O2 to the critical power model to derive the critical V[Combining Dot Above]O2. J Strength Cond Res XX(X): 000-000, 2021-The purposes of this study were to (a) determine whether the critical power (CP) model could be applied to V[Combining Dot Above]O2 to estimate the critical V[Combining Dot Above]O2 (CV[Combining Dot Above]O2) and (b) to compare the CV[Combining Dot Above]O2 with the V[Combining Dot Above]O2 at CP (V[Combining Dot Above]O2CP), the ventilatory threshold (VT), respiratory compensation point (RCP), and the CV[Combining Dot Above]O2 without the V[Combining Dot Above]O2 slow component (CV[Combining Dot Above]O2slow). Nine subjects performed a graded exercise test to exhaustion to determine V[Combining Dot Above]O2peak, VT, and RCP. The subjects performed 4 randomized, constant power output work bouts to exhaustion. The time to exhaustion (TLim), the total work (WLim), and the total volume of oxygen consumed with (TV[Combining Dot Above]O2) and without the slow component (TV[Combining Dot Above]O2slow) were recorded during each trial. The linear regressions of the TV[Combining Dot Above]O2 vs. TLim, TV[Combining Dot Above]O2slow vs. TLim, and WLim vs. TLim relationship were performed to derive the CV[Combining Dot Above]O2, CV[Combining Dot Above]O2slow, and CP, respectively. A 1-way repeated-measures analysis of variance (p ≤ 0.05) with follow-up Sidak-Bonferroni corrected pairwise comparisons indicated that CV[Combining Dot Above]O2 (42.49 ± 3.22 ml·kg-1·min-1) was greater than VT (30.80 ± 4.66 ml·kg-1·min-1; p < 0.001), RCP (36.74 ± 4.49 ml·kg-1·min-1; p = 0.001), V[Combining Dot Above]O2CP (36.76 ± 4.31 ml·kg-1·min-1; p < 0.001), and CV[Combining Dot Above]O2slow (38.26 ± 2.43 ml·kg-1·min-1; p < 0.001). However, CV[Combining Dot Above]O2slow was not different than V[Combining Dot Above]O2CP (p = 0.140) or RCP (p = 0.235). Thus, the CP model can be applied to V[Combining Dot Above]O2 to derive the CV[Combining Dot Above]O2 and theoretically is the highest metabolic steady state that can be maintained for an extended period without fatigue. Furthermore, the ability of the CV[Combining Dot Above]O2 to quantify the metabolic cost of exercise and the inefficiency associated with the V[Combining Dot Above]O2 slow component may provide a valuable tool for researchers and coaches to examine endurance exercise.