Whipp B J, Ward S A
Human Bio-Energetics Research Centre, Crickhowell, Powys, UK.
Eur Respir J. 2009 Jun;33(6):1254-60. doi: 10.1183/09031936.00110108.
Among the benefits expected to result from a therapeutic intervention in patients with impaired systemic functioning is an increase in exercise tolerance. For this a constant high-intensity work rate has been shown to provide a more sensitive index of improvement than the maximum work rate, or oxygen uptake, on a symptom-limited incremental test. However, the extremely large variability of the improvement in this particular index of tolerance undermines the ability to make general inferences for the underlying functional improvement. We argue that this is a necessary consequence of the particular work rate chosen for the test and the change in the parameters of the subject's hyperbolic power-duration relationship for that form of exercise: its "critical power" and "curvature constant". Without knowledge of these features, any absolute or per cent increase in tolerance time to a single constant-load exercise bout must be interpreted with caution regarding the physiological benefit(s) that have accrued from the intervention.
对于全身功能受损的患者，治疗干预预期带来的益处之一是运动耐力的提高。为此，在症状限制递增试验中，持续的高强度工作率已被证明比最大工作率或摄氧量能提供更敏感的改善指标。然而，这种特定耐力指标改善的极大变异性削弱了对潜在功能改善进行一般推断的能力。我们认为，这是该测试所选择的特定工作率以及该形式运动中受试者双曲线功率 - 持续时间关系参数变化的必然结果：其“临界功率”和“曲率常数”。如果不了解这些特征，对于单次恒定负荷运动 bout 的耐受时间的任何绝对增加或百分比增加，在解释干预所带来的生理益处时都必须谨慎。
