[Characteristics of exercise ventilation and gas exchange in obese and extremely obese patients]

Zhonghua Jie He He Hu Xi Za Zhi. 2019 Jan 12;42(1):20-23. doi: 10.3760/cma.j.issn.1001-0939.2019.01.007.
[Article in Chinese]

Abstract

Objective: To evaluate the characteristics of exercise ventilation and gas exchange in obese and extremely obese patients by Cardiopulmonary exercise test (CPX). Methods: Restrospective anal-ysis of subjects who underwent CPET in Shengjing Hospital of China Medical University from June 2014 to June 2017. A total of 74 subjects were enrolled. According to the body mass index (BMI), 74 subjects were divided into control group(18.5 kg/m(2)≤BMI<23.9 kg/m(2)) (n=21), obese group (28.0 kg/m(2)≤BMI<40.0 kg/m(2)) (n=30) and extremely obese group(BMI≥40.0 kg/m(2))(n=23), respectively. V(O2max), V(O2max)/kg, anaerobic thresh-old(AT), oxygen pulse(V(O2)/HR), breath reserve(BR), inhale time (VTin), expiratory time(VTex) and ventilato-ry equivalent for CO(2)(EqCO(2))were measured by CPX and compared by using one-way ANOVA. Results: Compared to the control group (1 620±400) L/min, the maximal oxygen uptake(V(O2max)) in obese group(1 905±592) L/min and extremely obese group (2 131.09±541.86) L/min were significance higher (F=5.14, P<0.01). The V(O2max)/kg in obese group (19±5) L·min(-1)·kg(-1) and extremely obese groups (16±4) L·min(-1)·kg(-1) were sig-nificant lower than those in control group(27±5)L·min(-1)·kg(-1) (F=35.37,P<0.01). Compared to the control group (9.3±1.4)L·min(-1)·W(-1), the change of oxygen uptake required under certain exercise load (ΔV(O2)/ΔWR) in obese group(9.0±1.7) L·min(-1)·W(-1)and extremely obese group (8.7±2.2) L·min(-1)·W(-1) were no significant difference (F=0.67,P=0.51). The AT in obese group (1 114±391) L/min and extremely obese group (1 348±349) L/min were significant higher than those in control group (832±223) L/min (F=12.85,P<0.01). Com-pared to the control group(10±4) L·min(-1)·b(-1), V(O2)/HR in obese group (12±3) L·min(-1)·b(-1) and extremely obese group(14±3) L·min·b(-1) were significance higher (F=8.16, P<0.01). No significant difference was found between the three groups in BR, VTin, VTex and EqCO(2). Conclusion: obese and extremely obese individu-als have a decreased ablity to exercise when the body requires anaerobic metabolism to provide energy. As exercise power increases, the heart oxygen consumption per stroke and the amount of volume and oxygen re-quired for gax exchange does increase.

目的: 通过心肺运动试验(CPX)评价肥胖与过度肥胖患者运动耐力与气体交换的特点。 方法: 回顾性分析2014年6月至2017年6月中国医科大学附属盛京医院肺功能室行心肺运动试验的患者资料。共入选74例,根据体重指数(BMI)分为对照组(18.5 kg/m(2)≤BMI<23.9 kg/m(2))21例,肥胖组(28.0 kg/m(2)≤BMI<40.0 kg/m(2))30例,过度肥胖组(BMI≥40.0 kg/m(2))23例,采用CPX测定各组心肺运动功能参数最大摄氧量(V(O2max))、公斤摄氧量(V(O2max)/kg)、无氧阈、氧脉搏(V(O2)/HR)、最大运动时呼吸储备(BR)、吸气时间(VTin)、呼气时间(VTex)和二氧化碳当量(EqCO(2))。3组间的各指标均数比较采用单因素方差分析。 结果: 肥胖组和过度肥胖组的V(O2max)分别为(1 905±592)和(2 131±542)L/min,均高于较对照组的(1 620±400)L/min(F=5.14,P<0.01);肥胖组和过度肥胖组的V(O2max)/kg分别为(19±5)和(16±4)L·min(-1)·kg(-1),均低于对照组(27±5)L·min(-1)·kg(-1)(F=35.37,P<0.01);在一定运动负荷下肥胖组和过度肥胖组所需的摄氧量(ΔV(O2)/ΔWR)分别为(9.0±1.7)和(8.7±2.2)L·min(-1)·W(-1),均低于对照组(9.3±1.4)L·min(-1)·W(-1)(F=0.67,P=0.51);肥胖组和过度肥胖组无氧阈分别为(1 114±391)和(1 348±349)L/min,均高于对照组(832±223)L/min(F=12.85,P<0.01);在运动达到最高运动状态时肥胖组和过度肥胖组氧脉搏分别为(12±3)和(14±3)L(-1)·min·b(-1),均高于对照组的(10±4)L·min(-1)·b(-1)(F=8.16,P<0.01);3组间BR、吸气时间、呼气时间和EqCO(2)差异无统计学意义(均P>0.05)。 结论: 肥胖者和过度肥胖者在机体需无氧代谢提供能量时的运动耐力下降。随着运动功率的增加,过度肥胖者心脏每搏耗氧量增加,且气体交换所需潮气量和耗氧量也增加。.

Keywords: Energy metabolism; Exercise test; Obesity.

MeSH terms

  • Body Mass Index
  • Cardiorespiratory Fitness / physiology
  • China
  • Exercise Test / methods
  • Exercise*
  • Humans
  • Obesity / physiopathology*
  • Oxygen Consumption / physiology*