Center for Tobacco Research, Division of Medical Oncology, Department of Internal Medicine, The Ohio State University, Columbus, OH.
Department of Internal Medicine, Rush University, Chicago, IL.
Med Sci Sports Exerc. 2024 Oct 1;56(10):2039-2048. doi: 10.1249/MSS.0000000000003481. Epub 2024 May 15.
Ventilatory constraints are common during exercise in children, but the effects of obesity and sex are unclear. The purpose of this study was to investigate the effects of obesity and sex on ventilatory constraints (i.e., expiratory flow limitation (EFL) and dynamic hyperinflation) during a maximal exercise test in children.
Thirty-four 8- to 12-yr-old children without obesity (18 females) and 54 with obesity (23 females) completed pulmonary function testing and maximal cardiopulmonary exercise tests. EFL was calculated as the overlap between tidal flow-volume loops during exercise and maximal expiratory flow-volume loops. Dynamic hyperinflation was calculated as the change in inspiratory capacity from rest to exercise.
Maximal minute ventilation was not different between children with and without obesity. Average end-inspiratory lung volumes (EILV) and end-expiratory lung volumes (EELV) were significantly lower during exercise in children with obesity (EILV: 68.8% ± 0.7% TLC; EELV: 41.2% ± 0.5% TLC) compared with children without obesity (EILV: 73.7% ± 0.8% TLC; EELV: 44.8% ± 0.6% TLC; P < 0.001). Throughout exercise, children with obesity experienced more EFL and dynamic hyperinflation compared with those without obesity ( P < 0.001). Also, males experienced more EFL and dynamic hyperinflation throughout exercise compared with females ( P < 0.001). At maximal exercise, the prevalence of EFL was similar in males with and without obesity; however, the prevalence of EFL in females was significantly different, with 57% of females with obesity experiencing EFL compared with 17% of females without obesity ( P < 0.05). At maximal exercise, 44% of children with obesity experienced dynamic hyperinflation compared with 12% of children without obesity ( P = 0.002).
Obesity in children increases the risk of developing mechanical ventilatory constraints such as dynamic hyperinflation and EFL. Sex differences were apparent with males experiencing more ventilatory constraints compared with females.
在儿童运动过程中，通气受限很常见，但肥胖和性别的影响尚不清楚。本研究的目的是探讨肥胖和性别对儿童最大运动试验中通气受限（即呼气流量限制（EFL）和动态过度充气）的影响。
34 名 8 至 12 岁无肥胖（18 名女性）和 54 名肥胖儿童（23 名女性）完成了肺功能测试和最大心肺运动测试。EFL 是通过运动期间的潮气流-容积环与最大呼气流量-容积环之间的重叠计算得出的。动态过度充气是通过从休息到运动时吸气容量的变化来计算的。
肥胖儿童和非肥胖儿童的最大分钟通气量没有差异。肥胖儿童在运动期间的平均吸气末肺容量（EILV）和呼气末肺容量（EELV）明显低于非肥胖儿童（EILV：68.8%±0.7%TLC；EELV：41.2%±0.5%TLC）（EILV：73.7%±0.8%TLC；EELV：44.8%±0.6%TLC；P<0.001）。在整个运动过程中，肥胖儿童经历的 EFL 和动态过度充气比非肥胖儿童多（P<0.001）。此外，男性在整个运动过程中经历的 EFL 和动态过度充气比女性多（P<0.001）。在最大运动时，肥胖男性和非肥胖男性的 EFL 患病率相似；然而，肥胖女性的 EFL 患病率差异显著，57%的肥胖女性经历 EFL，而非肥胖女性的 EFL 患病率为 17%（P<0.05）。在最大运动时，44%的肥胖儿童经历动态过度充气，而非肥胖儿童的这一比例为 12%（P=0.002）。
儿童肥胖增加了动态过度充气和 EFL 等机械通气受限的风险。男性比女性经历更多的通气受限，这表明存在性别差异。
