Collins Jessica, Leach Olivia, Dorff Abigail, Linde Jessica, Kofoed Jason, Sherman Megan, Proffit Meagan, Gifford Jayson R
Department of Exercise Sciences, Brigham Young University, Provo, Utah.
Program of Gerontology, Brigham Young University, Provo, Utah.
J Appl Physiol (1985). 2022 Oct 1;133(4):986-1000. doi: 10.1152/japplphysiol.00344.2022. Epub 2022 Sep 15.
Responses to exercise at a given percentage of one's maximum rate of oxygen consumption (V̇o), or percentage of the power associated with V̇o during a graded exercise test (i.e., P), vary. The purpose of this study was to determine if differences in critical power (P, maximum metabolic steady state) and work-prime (W', the amount of work tolerated above steady state) are related to training-induced changes in endurance. P, W', V̇o, and other variables were determined before and after 22 adults completed 8 wk of either moderate-intensity continuous training (MICT) or high-intensity interval training (HIIT) performed at fixed percentages of P. On average, P increased to a greater extent following HIIT (MICT: 15.7 ± 3.1% vs. HIIT: 27.5 ± 4.3%; = 0.03), but the magnitude of change varied widely within each group (MICT: 4%-36%, HIIT: 4%-61%). The intensity of the prescribed exercise relative to pretraining P, not P, accounted for most of the variance in changes to P in response to a given protocol ( = 0.61-0.64; < 0.01). Although P and V̇o were related before training ( = 0.92, < 0.01), the training-induced change in P was not significantly related to the change in V̇o ( = 0.06, = 0.26). Before training, time-to-failure at P was related to W' ( = 0.52; < 0.01), but not V̇o ( = 0.13; = 0.10) Training-induced changes in time-to-failure at the initial P were better captured by the combined changes in W' and P ( = 0.77, < 0.01), than by the change in V̇o ( = 0.24; = 0.02). Differences in P and W' account for some of the variability in responses to endurance exercise. As the highest percentage of V̇O at which steady state conditions can be achieved, a person's critical power (P) strongly influences the metabolic strain of a given exercise. In this study we demonstrate that training-induced changes in endurance are more strongly related to the intensity of an exercise training program, relative to P than relative to V̇o. Thus, exercise may be more homogenously and effectively prescribed in relation to P than traditional factors like V̇o.
在以个人最大耗氧率（V̇o）的给定百分比进行运动时，或者在分级运动测试中与V̇o相关的功率百分比（即P）下，运动反应存在差异。本研究的目的是确定临界功率（P，最大代谢稳态）和工作储备（W'，稳态之上耐受的工作量）的差异是否与训练引起的耐力变化有关。在22名成年人完成8周的中等强度持续训练（MICT）或高强度间歇训练（HIIT）（均以P的固定百分比进行）前后，测定了P、W'、V̇o和其他变量。平均而言，HIIT后P的增加幅度更大（MICT：15.7±3.1% vs. HIIT：27.5±4.3%；P = 0.03），但每组内变化幅度差异很大（MICT：4%-36%，HIIT：4%-61%）。相对于训练前的P，而非P本身，规定运动的强度解释了在给定方案下P变化的大部分方差（R² = 0.61-0.64；P < 0.01）。尽管训练前P和V̇o相关（R² = 0.92，P < 0.01），但训练引起的P变化与V̇o的变化无显著相关性（R² = 0.06，P = 0.26）。训练前，在P强度下的疲劳时间与W'相关（R² = 0.52；P < 0.01），但与V̇o无关（R² = 0.13；P = 0.10）。与V̇o的变化（R² = 0.24；P = 0.02）相比，W'和P的综合变化能更好地反映初始P强度下训练引起的疲劳时间变化（R² = 0.77，P < 0.01）。P和W'的差异解释了耐力运动反应中的一些变异性。作为能够实现稳态条件的最高V̇O百分比，一个人的临界功率（P）强烈影响给定运动的代谢压力。在本研究中，我们证明训练引起的耐力变化与运动训练计划的强度更密切相关，相对于P而言，比相对于V̇o更密切。因此，相对于V̇o等传统因素，基于P来规定运动可能更均匀、有效。
