Bodner Michael E, Rhodes Edward C, Martin Alan D, Coutts Kenneth D
School of Human Kinetics, University of British Columbia, Vancouver, BC V6T 1W5, Canada.
J Strength Cond Res. 2002 Nov;16(4):573-80.
The purpose of this study was to assess the relationship of the heart rate deflection point (HRDP) to the ventilatory threshold (VT) in trained cyclists. Twenty-one endurance-trained cyclists (mean +/- SD: Vo(2)max = 67.6 +/- 4.7 ml x kg x min(-1)) completed a maximal cycle ergometer test of volitional fatigue using a ramped protocol. Ventilatory variables (Ve, Vo(2), Vco(2)) and power were measured online with averages reported every 20 seconds. Heart rate (HR) was recorded every 20 seconds using a Polar monitor. VT was calculated using the excess CO(2) elimination curve. The first derivative of a logistic growth curve fit to the HR-power data produced the HRDP. No significant differences (p > 0.01) existed between HR values at HRDP (171.7 +/- 9.6 b x min(-1)) and VT (169.8 +/- 9.9 b x min(-1)) or between Vo(2) values at HRDP (53.6 +/- 4.2 ml x kg x min(-1)) and VT (52.2 +/- 4.8 ml x kg x min(-1)). But power values at HRDP (318.7 +/- 30.7 W) were significantly different (p < 0.01) from those at VT (334.8 +/- 36.7 W). There were significant relationships between HRDP and VT for the physiological variables of HR (r = 0.92, p < 0.001), Vo(2) (r = 0.72, p < 0.001), and power (r = 0.77, p < 0.001). These findings indicate that HR and Vo(2) at HRDP are not significantly different from the values at VT in trained cyclists. HR values derived from HRDP may be used to set parameters for training intensity. Variability in the speed/power-HRDP relationship across detrained/trained states may be used to evaluate training programs.
本研究的目的是评估训练有素的自行车运动员的心率转折点（HRDP）与通气阈值（VT）之间的关系。21名耐力训练的自行车运动员（平均±标准差：最大摄氧量=67.6±4.7 ml·kg·min⁻¹）使用递增方案完成了一项至意志性疲劳的最大自行车测力计测试。在线测量通气变量（每分钟静息通气量、摄氧量、二氧化碳排出量）和功率，每20秒报告一次平均值。使用Polar监测仪每20秒记录一次心率（HR）。使用过量二氧化碳消除曲线计算通气阈值。对HR-功率数据拟合的逻辑增长曲线的一阶导数得出心率转折点。心率转折点时的心率值（171.7±9.6次/分钟）与通气阈值时的心率值（169.8±9.9次/分钟）之间，以及心率转折点时的摄氧量值（53.6±4.2 ml·kg·min⁻¹）与通气阈值时的摄氧量值（52.2±4.8 ml·kg·min⁻¹）之间均无显著差异（p>0.01）。但心率转折点时的功率值（318.7±30.7 W）与通气阈值时的功率值（334.8±36.7 W）有显著差异（p<0.01）。心率转折点与通气阈值在心率（r = 0.92，p<0.001）、摄氧量（r = 0.72，p<0.001）和功率（r = 0.77，p<0.001）等生理变量方面存在显著关系。这些发现表明，训练有素的自行车运动员心率转折点时的心率和摄氧量与通气阈值时的值无显著差异。从心率转折点得出的心率值可用于设定训练强度参数。跨停训/训练状态的速度/功率-心率转折点关系的变异性可用于评估训练计划。
