Mattioni Maturana Felipe, Keir Daniel A, McLay Kaitlin M, Murias Juan M
Faculty of Kinesiology, University of Calgary, Canada.
School of Kinesiology, The University of Western Ontario, Canada.
J Sci Med Sport. 2017 Aug;20(8):795-799. doi: 10.1016/j.jsams.2016.11.023. Epub 2017 Jan 24.
Critical power (CP) demarcates the boundary between heavy and very heavy exercise intensity domains, and therefore, the power output (PO) that can be sustained at the maximal metabolic steady-state during constant-PO exercise (i.e., maximal lactate steady-state (MLSS)). However, the estimated CP does not always reflect a sustainable intensity of exercise, where blood lactate concentration ([La]) and oxygen uptake (V˙O) reach a plateau.
To test cyclists' ability to predict their highest PO associated with metabolic steady-state based on their own perception of effort.
Repeated measures.
Thirteen healthy young cyclists (26±3years; 69.0±9.2kg; 174±10cm) were tested. Five time-to-exhaustion trials were used to derive CP based on a 2-parameter hyperbolic model (CP). Participants performed two 30-min rides at a self-selected PO that they considered their highest sustainable exercise intensity (CP). Additionally, MLSS was determined as the highest PO at which variation in [La] ≤1.0mmolL between the 10th and 30th min was observed during a 30-min ride.
Mean PO at CP (233±42W) was similar (p>0.05) to MLSS (233±41W), whereas CP (253±44W) consistently overestimated (p<0.05) the PO associated to metabolic steady-state. The limits of agreement (LOA) between MLSS and CP were -20 to +20W (bias=0W, p>0.05), whereas the LOA between CP and CP were -40 to 0W (bias=-20W, p<0.05). CP and MLSS presented similar (p>0.05) metabolic response (i.e., V˙O, [La], and HR).
Compared to CP, CP may offer a more precise approach to predict the constant-PO associated with maximal physiological steady-state.
临界功率（CP）划分了重度和极重度运动强度域之间的界限，因此，它是在恒定功率输出（PO）运动期间（即最大乳酸稳态（MLSS））能够在最大代谢稳态下维持的功率输出。然而，估算的CP并不总是反映出血乳酸浓度（[La]）和摄氧量（V˙O）达到平台期时可持续的运动强度。
测试自行车运动员基于自身用力感知来预测与代谢稳态相关的最高PO的能力。
重复测量。
对13名健康年轻自行车运动员（26±3岁；69.0±9.2千克；174±10厘米）进行测试。使用五次力竭时间试验，基于双参数双曲线模型得出CP（临界功率）。参与者以他们认为是自身最高可持续运动强度（CP）的自我选择的PO进行了两次30分钟骑行。此外，将MLSS确定为在30分钟骑行期间第10至30分钟内[La]变化≤1.0毫摩尔/升时的最高PO。
CP时的平均PO（233±42瓦）与MLSS（233±41瓦）相似（p>0.05），而CP（253±44瓦）始终高估（p<0.0）与代谢稳态相关的PO。MLSS和CP之间的一致性界限（LOA）为-20至+20瓦（偏差=0瓦，p>0.05），而CP和CP之间的LOA为-40至0瓦（偏差=-20瓦，p<0.05）。CP和MLSS表现出相似（p>0.05）的代谢反应（即V˙O、[La]和心率）。
与CP相比，CP可能为预测与最大生理稳态相关的恒定PO提供更精确的方法。
