Marwood Simon, Parker Simpson Len, Wilkerson Daryl P, Jones Andrew M, Goulding Richie P
School of Health & Sport Sciences, Liverpool Hope University, Liverpool, UK.
Human Performance Science Research Group, University of Edinburgh, Edinburgh, UK.
Eur J Sport Sci. 2025 May;25(5):e12291. doi: 10.1002/ejsc.12291.
We examined the validity of the respiratory compensation point (RCP) in estimating critical power (CP) by determining the relative agreement between them following an acute intervention, hypoxia, which reduces RCP and CP. RCP and CP were determined in normoxia (N: FiO = 0.21) and hypoxia (H: FiO = 0.13) with RCP converted to a power output (W) via linear regression of the V̇O-time relationship with correction for the mean response time. RCP and CP were lower in hypoxia compared to normoxia (p < 0.001), but there was no difference between CP and RCP in N or H (N: 174 ± 26 (CP) vs. 178 ± 30 (RCP) W; H: 133 ± 19 (CP) vs. 139 ± 22 (RCP) W, p = 0.53). In both N (r = 0.32, p = 0.31) and H (r = 0.00, p = 0.99), RCP was not correlated with CP. Moreover, the 95% limits of agreement (LOA) were unacceptably wide (N: 3 ± 64 W; H: 7 ± 57 W). There was no correlation between the change in RCP and the change in CP caused by hypoxia (W: r = 0.32), with similarly poor 95% LOA (W: -3 ± 62 W). The weak correlations and wide LOA within and between conditions suggest little practical values in using RCP to estimate CP.
我们通过确定急性干预（低氧，可降低呼吸补偿点（RCP）和临界功率（CP））后两者之间的相对一致性，来检验RCP在估计CP方面的有效性。在常氧（N：吸入氧分数（FiO₂）=0.21）和低氧（H：FiO₂=0.13）条件下测定RCP和CP，通过对V̇O₂-时间关系进行线性回归并校正平均反应时间，将RCP转换为功率输出（W）。与常氧相比，低氧时RCP和CP均降低（p<0.001），但在N或H条件下，CP和RCP之间无差异（N：174±26（CP）对178±30（RCP）W；H：133±19（CP）对139±22（RCP）W，p=0.53）。在N（r=0.32，p=0.31）和H（r=0.00，p=0.99）条件下，RCP与CP均无相关性。此外，95%一致性界限（LOA）过宽（N：3±64W；H：7±57W）。低氧引起的RCP变化与CP变化之间无相关性（W：r=0.32），95%LOA同样较差（W：-3±62W）。不同条件下及条件之间的弱相关性和较宽的LOA表明，使用RCP估计CP几乎没有实际价值。
