Marinus Nastasia, Bervoets Liene, Massa Guy, Verboven Kenneth, Stevens An, Takken Tim, Hansen Dominique
REVAL (Rehabilitation Research Center), BIOMED (Biomedical Research Center), Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium.
Faculty of Medicine and Life Sciences, Hasselt University, Hasselt, Belgium.
J Sports Med Phys Fitness. 2017 Dec;57(12):1687-1694. doi: 10.23736/S0022-4707.16.06607-X. Epub 2016 Oct 20.
Cardiopulmonary exercise testing is advised ahead of exercise intervention in obese adolescents to assess medical safety of exercise and physical fitness. Optimal validity and reliability of test results are required to identify maximal exercise effort. As fat oxidation during exercise is disturbed in obese individuals, it remains an unresolved methodological issue whether the respiratory gas exchange ratio (RER) is a valid marker for maximal effort during exercise testing in this population.
RER during maximal exercise testing (RERpeak), and RER trajectories, was compared between obese and lean adolescents and relationships between RERpeak, RER slope and subject characteristics (age, gender, Body Mass Index [BMI], Tanner stage, physical activity level) were explored. Thirty-four obese (BMI: 35.1±5.1 kg/m²) and 18 lean (BMI: 18.8±1.9 kg/m²) adolescents (aged 12-18 years) performed a maximal cardiopulmonary exercise test on bike, with comparison of oxygen uptake (VO2), heart rate (HR), expiratory volume (VE), carbon dioxide output (VCO2), and cycling power output (W).
RERpeak (1.09±0.06 vs. 1.14±0.06 in obese vs. lean adolescents, respectively) and RER slope (0.03±0.01 vs. 0.05±0.01 per 10% increase in VO2, in obese vs. lean adolescents, respectively) was significantly lower in obese adolescents, and independently related to BMI (P<0.05). Adjusted for HRpeak and VEpeak, RERpeak and RER slope remained significantly lower in obese adolescents (P<0.05). RER trajectories (in relation to %VO2peak and %Wpeak) were significantly different between groups (P<0.001).
RERpeak is significantly lowered in obese adolescents. This may have important methodological implications for cardiopulmonary exercise testing in this population.
建议在对肥胖青少年进行运动干预之前进行心肺运动测试，以评估运动的医学安全性和体能。为了确定最大运动强度，需要测试结果具有最佳的有效性和可靠性。由于肥胖个体运动期间的脂肪氧化受到干扰，在该人群的运动测试中，呼吸气体交换率（RER）是否是最大运动强度的有效指标仍是一个未解决的方法学问题。
比较肥胖青少年和瘦青少年在最大运动测试期间的RER（RERpeak）和RER轨迹，并探讨RERpeak、RER斜率与受试者特征（年龄、性别、体重指数[BMI]、坦纳分期、身体活动水平）之间的关系。34名肥胖青少年（BMI：35.1±5.1kg/m²）和18名瘦青少年（BMI：18.8±1.9kg/m²）（年龄12 - 18岁）进行了自行车最大心肺运动测试，比较了摄氧量（VO2）、心率（HR）、呼气量（VE）、二氧化碳排出量（VCO2）和骑行功率输出（W）。
肥胖青少年的RERpeak（分别为1.09±0.06与瘦青少年的1.14±0.06）和RER斜率（肥胖青少年每10%VO2增加分别为0.03±0.01与瘦青少年的0.05±0.01）显著更低，且与BMI独立相关（P<0.05）。在调整HRpeak和VEpeak后，肥胖青少年的RERpeak和RER斜率仍然显著更低（P<0.05）。两组之间的RER轨迹（相对于%VO2peak和%Wpeak）显著不同（P<0.001）。
肥胖青少年的RERpeak显著降低。这可能对该人群的心肺运动测试具有重要的方法学意义。
