Drinkard Bart, Roberts Mary D, Ranzenhofer Lisa M, Han Joan C, Yanoff Lisa B, Merke Deborah P, Savastano David M, Brady Sheila, Yanovski Jack A
Rehabilitation Medicine Department, Mark O. Hatfield Clinical Research Center, National Institutes of Health, Bethesda, MD, USA.
Med Sci Sports Exerc. 2007 Oct;39(10):1811-6. doi: 10.1249/mss.0b013e31812e52b3.
Peak oxygen uptake (VO2peak) is frequently difficult to assess in overweight individuals; therefore, submaximal measures that predict VO2peak are proposed as substitutes. Oxygen uptake efficiency slope (OUES) has been suggested as a submaximal measurement of cardiorespiratory fitness that is independent of exercise intensity. There are few data examining its value as a predictor of V O2peak in severely overweight adolescents.
One hundred seven severely overweight (BMI Z 2.50 +/- 0.34) and 43 nonoverweight (BMI Z 0.13 +/- 0.84) adolescents, performed a maximal cycle ergometer test with respiratory gas-exchange measurements. OUES was calculated through three exercise intensities: lactate inflection point (OUES LI), 150% of lactate inflection point (OUES 150), and VO2peak (OUES PEAK).
When adjusted for lean body mass, VO2peak and OUES at all exercise intensities were lower in overweight subjects (VO2peak: 35.3 +/- 6.4 vs 46.8 +/- 7.9 mL.kg(-1) LBM.min(-1), P < 0.001; OUES LI: 37.9 +/- 10.0 vs 43.7 +/- 9.2 mL.kg(-1) LBM.min(-1).logL(-1) P < 0.001; OUES 150: 41.6 +/- 9.0 vs 49.8 +/- 11.1 mL.kg(-1) LBM.min(-1).logL(-1) P < 0.001; and OUES PEAK: 45.1 +/- 8.7 vs 52.8 +/- 9.6 mL.kg(-1) LBM.min(-1).logL(-1) P < 0.001). There was a significant increase in OUES with increasing exercise intensity in both groups (P < 0.001). OUES at all exercise intensities was a significant predictor of VO2peak for both groups (r2 = 0.35-0.83, P < 0.0001). However, limits of agreement for predicted VO2peak relative to actual VO2peak were wide (+/- 478 to +/- 670 mL.min(-1)).
OUES differs significantly in overweight and nonoverweight adolescents. The wide interindividual variation and the exercise intensity dependence of OUES preclude its use in clinical practice as a predictor of VO2peak.
超重个体的最大摄氧量（VO2peak）常常难以评估；因此，有人提出用预测VO2peak的次最大运动量指标作为替代。摄氧效率斜率（OUES）被认为是一种与运动强度无关的次最大运动量心肺适能测量指标。关于其作为严重超重青少年VO2peak预测指标价值的数据较少。
107名严重超重（BMI为2.50±0.34）和43名非超重（BMI为0.13±0.84）青少年进行了带有呼吸气体交换测量的最大运动强度蹬车测试。通过三种运动强度计算OUES：乳酸拐点（OUES LI）、乳酸拐点的150%（OUES 150）和VO2peak（OUES PEAK）。
调整瘦体重后，超重受试者在所有运动强度下的VO2peak和OUES均较低（VO2peak：35.3±6.4 vs 46.8±7.9 mL·kg（-1）瘦体重·min（-1），P<0.001；OUES LI：37.9±10.0 vs 43.7±9.2 mL·kg（-1）瘦体重·min（-1）·logL（-1），P<0.001；OUES 150：41.6±9.0 vs 49.8±11.1 mL·kg（-1）瘦体重·min（-1）·logL（-1），P<0.001；OUES PEAK：45.1±8.7 vs 52.8±9.6 mL·kg（-1）瘦体重·min（-1）·logL（-1），P<0.001）。两组中，随着运动强度增加，OUES均显著升高（P<0.001）。所有运动强度下的OUES都是两组VO2peak的显著预测指标（r2 = 0.35 - 0.83，P<0.0001）。然而，预测VO2peak相对于实际VO2peak的一致性界限较宽（±478至±670 mL·min（-1））。
超重和非超重青少年的OUES存在显著差异。OUES个体间差异大且依赖运动强度，这使其无法在临床实践中用作VO2peak的预测指标。
