慢性阻塞性肺疾病患者运动能力与通气效率的相关性分析

目的:通过分析二氧化碳通气当量和运动能力的关系,探讨稳定期慢性阻塞性肺疾病(COPD)患者运动中通气效率与最大运动能力的相关性。方法:选取54例稳定期COPD患者,行运动心肺功能测试,实时监测摄氧量(VO2)、分钟通气量(VE)和二氧化碳排出量(VCO2),根据公式:EqCO2=VE/VCO2计算得出静态二氧化碳通气当量(EqCO2rest)、无氧阈时二氧化碳通气当量(EqCO2at)和最大运动状态下的二氧化碳通气当量(EqCO2max)。结果:1.EqCO2rest、EqCO2at及EqCO2max呈递减趋势,差异有统计学意义(P=0.001)。2.EqCO2at与最大摄氧量(VO2max)(r=-0.294,P<0.05)、EqCO2max与VO2max(r=-0.301,P<0.05)均呈负相关;EqCO2rest与最大摄氧量占预计值的百分比(VO2max/Pred)呈负相关(r=-0.345,P<0.05)。3.肺功能GOLD 3级患者(21例)的VO2max(15.99±3.39)mL·min-1·kg-1明显低于GOLD 2级患者(25例)的VO2max[(18.88±5.36)mL·min-1·kg-1,P=0.038]。两组的EqCO2rest、EqCO2at及EqCO2max差异无统计学意义。结论:稳定期COPD患者运动中通气效率呈进行性下降趋势,这可能是导致其运动能力下降的重要因素之一。     

慢性阻塞性肺疾病患者营养状态对运动心肺功能的影响

目的：探讨营养状态对慢性阻塞性肺疾病（COPD）患运动心肺功能的影响。方法：43例COPD患分为营养不良组（15例），营养正常组（28例）和健康志愿（20名）进行负荷连续递增的运动心肺功能试验。运动行营养评价和常规肺功能检查，结果：（1）COPD营养不良组最大氧耗量（VO2max）、最大运动负荷（Wmax）、最大氧脉搏（O2pulsemax)和无氧阈（AT）低于营养正常组，两组比较差异有显性（P＜0．05）。通气氧耗（VO2／W／VE)和最大运动时的气急指数（DImax)与营养正常组比较，差异有显性（P＜0．05）。（2）COPD患理想体重百分比（IBW％）与VO2max占预计值百分比、Wmax占预计值百分比、O2pulsemax占预计值百分比，AT呈正相关（r=0.696,0.432,0.717,0.822,P均＜0．01）、与DImax,VO2/W/VE呈负相关（r=-0.450,-0.640,P均＜0．01）。结论：营养不良可以导致COPD患肌肉有氧代谢能力和运动耐力降低。     

心肺运动试验对合并营养风险的老年COPD病人心肺功能的评估研究

目的采用心肺运动试验(CPET),探讨合并营养风险的老年慢性阻塞性肺疾病(COPD)病人的心肺功能。方法根据营养风险筛查2002(NRS-2002)标准,对入选的68例中重度COPD病人进行营养风险评估,分为无营养风险组(n=30)及有营养风险组(n=38)。采用CPET及6 min步行试验(6MWT)评估2组病人心肺功能,观察2组间最大分钟通气量(VE max)、第1秒用力呼气容积(FEV1)、第1秒用力呼气容积占预计值的百分比(FEV1%pre)、FEV1/用力肺活量(FVC)、峰值摄氧量(VO_2peak)、最大代谢当量(METs)、无氧阈(AT)、最大功率负荷(WR max)、氧脉搏(O2pulse)、每公斤体质量最大摄氧量(VO_2max/kg)、6 min步行距离(6MWD)等指标是否有差异。结果有营养风险组VO_2peak、METs、AT、O_2pulse、WRmax等指标均显著低于无营养风险组(P0. 05); 2组间VEmax、FEV1、FEV1/FVC、6MWD差异无统计学意义(P0. 05)。结论 CPET评估合并有营养风险的老年COPD病人,能早期了解病人的心肺功能,为老年COPD病人制定营养处方提供依据,以便早期帮助COPD病人心肺功能康复,同时,CPET评估较6MWT更为灵敏。     

心肺运动试验在老年慢性阻塞性肺疾病中应用

目的 探讨心肺运动试验(CPET)评估老年慢性阻塞性肺疾病(COPD)患者肺功能、运动能力、气体交换和血流动力学反应的特点，并探讨各项指标在COPD临床诊治过程中的意义。方法 选取2019年11月至2023年3月在吉林大学第一医院呼吸与危重症医学科就诊的稳定期COPD患者53例为试验组，同期体检健康志愿者52例为对照组。两组均行肺功能检查(PFT)及CPET,记录相关参数并进行比较，且分析PFT与CPET评估两组各项指标的差异。结果 PFT结果显示试验组第1秒用力呼气末容积(FEV1)、FEV1占预计值百分比(FEV1%pred)、用力肺活量(FVC)、FVC占预计值百分比(FVC%pred)、呼吸峰流量(PEF)、PEF占预计值百分比(PEF%pred)、最大肺活量(VC)、VC占预计值百分比(VC%pred)、FEV1/FVC均低于对照组，差异有统计学意义(P<0.05)。CPET检查结果显示，两组峰值心率(HRmax)、HRmax占预计值百分比(HRmax%pred)均无统计学意义(P>0.05),而试验组峰值功率(Wmax)、峰值功率占预计值百分比(Wmax%pre...     

吸入异丙托溴胺对慢性阻塞性肺疾病患者运动肺功能的影响

目的 评价吸入异丙托溴胺(ipratropium bromide,IPB)是否改善慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)患者的静态肺功能,运动通气功能和运动耐量.方法 随机抽取稳定期COPD患者12例,吸入IPB溶液2 mg,吸人前后分别进行静态肺功能和运动肺功能测定.结果 吸入IPB后,COPD患者最大运动功率(Wmax)、最大耗氧量(VO2max)、最大运动时每分钟通气量(Vemax)和比潮气量(Vtmax/IC),较吸人前均有显著增加;死腔通气(VD/VT)和二氧化碳通气当量(Vemax/VCO2max)无明显改变.Vtmax/IC的变化(⊿Vtmax/IC)与VO2max的变化(⊿VO2max)有显著相关性(r=0.598,P＜0.05);⊿Vtmax/IC与最大运动功率的变化(⊿Wmax)也存在显著相关性(r=0.743,P＜0.05).结论 吸入IPB能够增加COPD患者的运动耐量,COPD患者吸入IPB后,⊿Vtmax/IC可能是运动耐量增加机制中的一个重要环节.     

先天性心脏病患者运动心肺功能表现

目的探讨先天性心脏病患者运动负荷测验特点。方法15例患者，男4例，女11例。其中房缺9例，室缺6例。并与年龄相近健康男性4例、女性11例作对照。进行踏车递增负荷运动测验。结果先天性心脏病组VO2max，VO2max占预计值％（＜正常84％）低于对照组；VO2AT，VO2AT／VO2maxpred低于对照组但在正常范围内；此外VO2／HRmax＜VO2／HRmaxpred。有3例心导管证实为肺动脉高压者，运动后PaO2及SaO2减低；P（A－a）O2加宽；P（a－et）CO2正值；VE／VCO2AT异常增高超过45，但BRmax正常。结论先天性心脏病患者运动负荷表现为最大有氧代谢能力减低。VE／VCO2AT异常增高为肺动脉高压、V／Q比率失调、肺循环障碍提供线索。运动后低血氧考虑有右至左分流。     

稳定期COPD患者静息肺功能测定及与最大摄氧量的相关性分析

目的探讨慢性阻塞性肺疾病（COPD）患者静息肺功能、运动耐力变化及两者的关系。方法选择32例稳定期COPD患者（COPD组）和20例健康体检者（对照组）,分别行静息肺功能测定和症状自限最大运动负荷递增试验,记录用力肺活量（FVC）、第1秒用力肺活量（FEV1．0）、FEV1．0占预计值百分比（FEV1．0％）、最大通气量（MVV）、静息状态下一氧化碳弥散量（DLCO）和最大摄氧量（VO2 max）;对COPD静息肺功能指标与VO2 max的关系行直线相关分析。结果COPD组FVC、FEV1．0、FEV1．O％、FEV1．0／FVC、MVV、DLCO和VO2 max均显著低于对照组（P均〈0．05）;COPD组FVC、FEV1．0、FEV1．0％、FEV1．0／FVC、MVV和DLCO与VO2 max均呈显著正相关（P均〈0．05）。结论稳定期COPD患者静息肺功能及运动耐力均有所减退,且两者呈正相关;联合检测此两项指标可综合评价COPD病情进展、预后及指导康复治疗。     

CPET评估制定运动处方指导下的有氧运动对COPD患者心肺功能的影响

目的探讨应用心肺运动试验评估制定的运动处方指导下的有氧运动对稳定期慢性阻塞性肺病(chronic obsturctive pulmonary disease,COPD)患者心肺功能的影响。方法入选220例COPD患者,分为对照组100例和观察组120例,入组评估心肺运动试验(cardiopulmonary exercise testing,CPET)和6分钟步行试验(6 minute walk test,6MWT)。测得6分钟步行距离(6MWD)、最大摄氧量(VO_2max)、最大代谢当量(METs)、无氧阈(AT)、功率负荷(Work rate,WR)、用力肺活量(FVC)、第1秒用力呼气容积(FEV1)、FEV1/FVC、FEV1/pre%等指标。对照组常规药物治疗和日常活动,观察组在此基础上,根据CPET评估,制定运动处方,根据AT值确定运动强度,训练12周后复查上述指标。结果观察组康复训练12周后,各项指标结果与干预前比较显示:6MWD增加105.56m,VO_2max增加253.99ml/min,代谢当量增加1.25METs,AT值增加148.15ml/min,WRmax增加19.34W,上述各项值与干预前比较均有统计学意义(P0.05)。肺功能指标均有统计学意义(P0.05)。结论应用CPET评估心肺功能,制定个体化运动处方,指导稳定期COPD患者康复运动训练,能有效改善患者心肺功能。     

慢性阻塞性肺疾病伴肺动脉高压对运动中气体交换的影响

目的:通过比较中重度慢性阻塞性肺疾病相关肺动脉高压(COPD-PH),与慢性阻塞性肺疾病无肺动脉高压(COPD-non PH),在运动中气体交换及运动耐量的差异,旨在为COPD-PH临床诊断、鉴别诊断、评估提供一定参考价值。方法:对54例处于稳定期的中重度慢性阻塞性肺疾病(COPD)患者依据肺动脉收缩压(PASP)分为两组,比较两组间血气分析、常规肺功能(PFT)、心肺运动试验(CPET)。结果:血气分析:COPD-PH的动脉氧分压(Pa O2)明显低于COPD-non PH(P0.01)。PFT:COPD-PH的第一秒用力呼气量(FEV1)、第一秒用力呼气量占预计值的百分比(FEV1%pred)及一氧化碳弥散量(DLco)均低于COPD-non PH(P0.05)。CPET:COPD-PH的峰值功率(Peak Load)、峰值摄氧量(Peak VO2)、峰值公斤摄氧量(Peak VO2/kg)、峰值分钟通气量(Peak VE)、Peak VE%pred及峰值氧脉搏(Peak O2pulse)均明显低于COPD-non PH(P0.01)。COPD-PH的峰值摄氧量占预计值的百分比(Peak VO2%pred)低于COPD-non PH(P0.05)。Pearson相关分析:PASP与DLco、Pa O2、Peak Load、Peak VO2及Peak O2pulse均呈负相关(P0.01)。结论:COPD-PH会导致患者肺换气功能明显受损、运动耐力明显下降,其降低程度与PASP存在相关性。对COPD行CPET,有助于早期发现COPD-PH。     

肺栓塞患者运动耐力的评估

目的:探讨心肺运动试验(CPET)与6min步行实验(6MWT)、左室射血分数(LVEF)评估肺栓塞(PE)患者运动耐受能力的相关性。方法:17例确诊断为PE的患者经最佳治疗后,出院前给予CPET、6MWT以及超声心动图。结果:(1)6min步行距离与峰值氧耗(VO2peak)明显相关(r=0.667,P0.01);6min步行距离与无氧阈值氧耗(VO2AT)、二氧化碳通气斜率(VE/VCO2slope)均无相关性(r=0.458,r=-0.456,P0.05)。(2)LVEF与VO2peak、VO2AT、VE/VCO2slope均无相关性(r=0.435,r=0.357,r=-0.426,P0.05)。结论:6MWT能准确可靠地评估PE患者的运动耐受能力。     

摄氧量平均反应时间在重度慢性阻塞性肺疾病患者心肺功能评估中的应用研究

目的 探讨重度慢性阻塞性肺疾病(COPD)患者在心肺运动试验(cardiopulmonary exercise test,CPET)检测零负荷热身期中的摄氧量动力学改变特点,研究零负荷热身期间摄氧量平均反应时间(mean response time,MRT)与COPD患者心肺功能及常规肺功能的相关性,探讨MRT值评价重...     

重度慢性阻塞性肺疾病患者运动过程中摄氧动力学变化特点研究

目的 研究摄氧量动力学在重度慢性阻塞性肺疾病(COPD)患者心肺运动试验(cardiopulmonary exercise test,CPET)检测中的变化特点,探讨COPD严重程度对摄氧动力学的影响.方法对20例Ⅲ级COPD、17例Ⅳ级COPD患者及18名正常健康者进行常规肺功能检测(pulmonary functi...     

The body weight-walking distance product as related to lung function, anaerobic threshold and peak VO2 in COPD patients.

The product of walking distance and body weight (D x W) mimics the work of walking. We hypothesized the superiority of D x W to walking distance (D) alone in any correlation with lung function, anaerobic threshold (AT) and maximal oxygen uptake (VO2max). We further hypothesized that the D x W product for a 6-min walk test (6 MWT) would correlate with the AT and VO2max because all three are markers of exercise ability. Thirty-three male chronic obstructive pulmonary disease (COPD) patients with mean forced expiratory volume in 1 sec (FEV1) of 1.2+/-0.4 l (range 0.58-1.86 l) were enrolled. Six patients were excluded due to inability to achieve a maximal test. Lung function and self-assessed every-day activities using a oxygen-cost diagram were evaluated before entry of the study. A maximal effort ramp-pattern cardiopulmonary exercise test (CPET) and a 6 MWT were conducted in random order. Borg score, heart rate, and O2 saturation with pulse oximetry (SpO2) were measured during both exercise tests. VO2 AT and minute ventilation were also measured during the CPET. Correlations were sought between the distance covered in the 6 MWT, and the D x W product with AT, VO2max and other variables. The average D and D x W were 456 m and 27.5 kg km(-1), respectively. D x W was superior to D alone when correlated with the VO2max and AT determined from the CPET, while modestly correlated with the change (delta) in Borg score and delta SpO2 in the 6 MWT and self-assessed every-day activities. Distance x weight product was correlated with the AT and VO2max. In addition, D x W was better correlated with diffusing capacity for carbon monoxide and vital capacity than D alone. We conclude that D x W mimics the work of walking better than D and is suggested as a parameter for evaluation of patients' fitness if gas exchange measurements are not available.     

冠心病单支血管病变患者PCI术前后及心脏康复后心肺运动试验指标的变化

目的 评估单支血管病变的冠心病患者接受经皮冠状动脉介入（PCI）治疗后心肺运动试验（CPET）各项指标的变化，探讨单支冠脉病变介入治疗对患者运动耐量及持续运动能力的改变。 方法 入选接受PCI治疗的单支血管病变冠心病患者144例，支架术后来院随访复查患者79例。收集所有受试者术前、术后即刻以及术后随访中CPET各项指标并分析其变化，进一步说明PCI前后活动耐量及坚持心脏康复的长期疗效。 结果 术前CPET中8例患者出现运动试验阳性；术后有1例阳性，随访复查中无阳性，术后患者CPET阳性率显著降低（P<0.05）。相较于术前，患者的运动持续时间[（8±4）minvs（10±4）min]、峰值METs（4.6±1.2 vs 5.1±0.6）、峰值公斤摄氧量[（16±4）ml/（kg·min）vs（17±4）]均有显著统计学差异（P<0.01）。最后，对比术后即刻数据，随访时持续运动时间[（10±4）minvs （11±5）min]、静息心率[（70±9）次/min vs（68±6）次/min]、AT时公斤摄氧量[（11.3±2.6）ml/（kg·min） vs （11.5±2.4）ml/（kg·min）]、达AT时 METs（3.51±0.82 vs 3.75±0.96）、峰值公斤摄氧量[（17±5）ml/（kg·min） vs （19±4）ml/（kg·min）]等指标均有明显改善（均P<0.05）。 结论 单支血管病变的冠心病患者在接受PCI治疗后即刻行CPET结果显示，胸痛症状改善、运动持续时间增加、峰值摄氧量提高，进一步说明PCI能改善患者运动时缺血症状，明显缓解症状，使患者持续运动能力得以提高。根据CPET制定的运动处方进行心脏康复后进行随访发现，心肺功能各项指标有显著改善      

心肺运动试验预测肺癌侵及血管的患者术后呼吸衰竭的探讨

目的探讨心肺运动试验预测肺癌侵及血管的患者术后呼吸衰竭的探讨。方法术前采用运动负荷递增的方案对172例原发性肺癌患者行心肺运动试验,测定终止负荷运动时的功率（W％）、最大摄氧量（VO2％P）、公斤氧耗量（VO2／kg）、无氧阁（AT）、代谢当量（MET）、氧脉搏（VO2／HR）、呼吸频率（BF）、通气鼙（VE）。结果1．运动心肺功能试验各项指标在肺叶切除术后呼衰和非呼衰组间均无显著性差异（P〉0．05）。全肺切除术而言,W％、VO2％P、VO2／kg、MET、VE、BF在术后呼衰组均较非呼衰组降低（P〈0．05或0．01）。2．W％、V02％P、VO2／kg、MET在行左全肺切除术术后呼衰组较非呼衰组降低（P〈0．05或0．01）。右全肺切除组仅BF在纰间差异有显著性意义（P〈0．05）。3．x0检验显示,六项指标不同程度异常与全肺切除术后呼衰的发牛率有关,logistic回归分析娃示MET〈4和BF〈30次／分与全肺切除术后呼衰的发生密切相关,V02／kg〈14．6ml／min／kg与左全肺切除术后呼衰的发生关系密切。4．术后全肺切除组VO2％P〈60％、BF〈30次／分、VE〈35L／min的敏感性和特异性均〉60％,阴性预测值均大于90％。左全肺切除组W％、VO2％P〈60％的敏感性和特异性均〉80％,阴性预测值100％,均高于VO2／kg。结论运动心肺功能试验对于有血管侵及的肺癌患者行全肺切除术,特别是行左全肺切除术,预测术后的呼吸衰竭、为全肺切除术的适应症评估提供依据,均具有重要意义。选择VO2％P作为预测术后呼衰、评估手术适应症的指标。因MET〈4、VO2／kg〈14．6ml／min／kg与肺切除术后呼衰关系密切,应结合临床情况适当考虑。     

Relationship of respiratory drives to dyspnea and exercise performance in chronic obstructive pulmonary disease

Frequently, patients with COPD with similar spirometric impairment have marked differences in dyspnea and exercise limitation. As the classic "blue bloater" with attenuated respiratory drive is described as being less dyspneic than his "pink puffer" counterpart, we wondered whether the variability in dyspnea and exercise tolerance in a group of patients with COPD with relatively similar degrees of air-flow obstruction might be partly explained by the variability in resting respiratory drives (unstimulated P0.1 and hypoxic and hypercapnic P0.1 responses). Therefore, we measured unstimulated mouth occlusion pressure (P0.1), hypoxic response (-delta P0.1/delta SaO2), hypercapnic response (delta P0.1/delta PCO2), 6-min walk distance, VO2max, steady-state exercise VE/VO2, exercise SaO2, and dyspnea using an oxygen cost diagram in 15 subjects with severe COPD (mean FEV1% 35.2 +/- 1.9 SEM). No correlations between spirometric impairment and either dyspnea or exercise performance were seen. Unstimulated P0.1 correlated inversely with spirometric impairment but did not correlate with dyspnea, VO2max or 6-min walk distance. Both hypoxic and hypercapnic responses were significantly correlated with greater exercise ventilation (VE/VO2), less exercise O2 desaturation, and a greater VO2max, but not with dyspnea or 6-min walk distance. The results of this study do not support the concept that depressed respiratory drives are associated with less dyspnea or greater exercise capability in COPD.     

Exercise capacity of thoracotomy patients in the early postoperative period

OBJECTIVE: We investigated the mechanism involved with the initial drop and subsequent recovery of exercise capacity in the early postoperative period of thoracotomy patients. METHODS: Sixteen patients (13 who had undergone lobectomy, 3 who had undergone pneumonectomy) underwent a routine pulmonary function test (PFT) and a cardiopulmonary exercise test preoperatively, within 14 postoperative days (POD; post-1; mean +/- SD, 9 +/- 2 POD), and after 14 POD (post-2; mean, 26 +/- 12 POD). RESULTS: After surgery on post-1, PFT results of FVC, FEV(1), and maximum ventilatory volume (MVV) significantly decreased. Oxygen uptake (VO(2)) at a venous blood lactate level of 2.2 mmol/L (La-2. 2), which was adopted as the empirical anaerobic threshold, and maximum V O(2) (VO(2)max) decreased significantly to 88.2 +/- 7.9% and 73.1 +/- 15.4% of the preoperative values, respectively. La-2.2 min ventilation (VE)/ MVV and maximum VEmax)/MVV increased significantly from 0.36 +/- 0.08 to 0. 66 +/- 0.20 and from 0.58 +/- 0.14 to 0.80 +/- 0.09, respectively. On post-2, though La-2.2 VO(2) did not change, VO(2)max improved significantly to 81.5 +/- 19.7% of the preoperative values, in association with significant increases in maximal tidal volume and VEmax, which were produced by significant increases in the PFT results. La-2.2 VE/MVV also decreased significantly to 0.49 +/- 0.13, which indicated a sufficient recovery of respiratory reserve at submaximal exercise. CONCLUSIONS: The initial drop of exercise capacity after lung resection seems to be derived from both circulatory and ventilatory limitations. Further, the subsequent recovery within 1 month seems to be produced by an improvement in ventilatory limitation, which was caused by the surgical injury to the chest wall.     

Impaired exercise performance and pulmonary function in elite cyclists during low-level ozone exposure in a hot environment

We evaluated the effects of low concentrations of ozone on the exercise performance and pulmonary function of 17 top-caliber endurance cyclists under conditions simulating competition and realistic temperature (31 degrees C). Each subject was randomly exposed to filtered air (FA), 0.12 and 0.20 ppm O3 on separate days in an environmental chamber. Each subject attempted to maintain submaximal exercise on a cycle ergometer equivalent to approximately 70% of maximal oxygen consumption (VO2max) for 60 min, followed by incremented (maximal) exercise until exhaustion. During submaximal exercise, average minute ventilation (VE) (89 L/min), VO2 (51 ml/min/kg or 72% VO2max), work load (260 W), and work time (57 min) were similar across all exposures. During maximal exercise, average peak VE (150 L/min), VO2 (68 ml/min/kg), work load (382 W), and ride time (263 s) were similar between 0.12 ppm O3 and FA. However, significant reductions in peak VE (18%), VO2 (16%), tidal volume (22%), work load (8%), and ride time (30%) occurred in 0.20 ppm O3 compared with those in FA. Postexercise decrements in forced expired volume in one second (FEV1) averaged 5.6% and 21.6% in 0.12 and 0.20 ppm O3, respectively. Ozone-related symptoms were mild in 0.12 ppm O3 but intensified and probably limited maximal performance in 13 subjects in 0.20 ppm O3. Changes in carbon monoxide diffusing capacity (adjusted for alveolar volume) were not significant across exposures. Nine subjects showed histamine hyperresponsiveness (i.e., greater than 20% decrease from the control postdiluent FEV1) after exposure to 0.20 ppm O3 as compared with 1 subject in 0.12 ppm O3.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ventilatory response of moderately obese women to submaximal exercise

To investigate the effect of moderate obesity on ventilatory responses to graded exercise, we compared the ventilatory responses of ten moderately obese (35 +/- 5 percent body fat) and nine leaner women (22 +/- 2 percent body fat) during walking on a treadmill with incremental increases in percent grade. Speed remained constant at 3.0 mph. In the obese women, VO2 in l/min and ml/FFW/min, fb (b/min), VE (l/min), and HR were significantly greater (P less than 0.05) at all four absolute workloads. At 10.0 and 12.5 percent grade, VO2 (ml/kg/min) was smaller and VE/VO2 was greater in the obese women. The difference in VE/VO2 suggests a lower ventilatory threshold for the obese women. Percent VO2 max and R (VCO2/VO2) were significantly different at 12.5 percent grade only. When VO2 was divided by HR (oxygen pulse), the two groups were not significantly different at any of the four workloads tested. The groups were compared further at workloads representing approximately 55, 65, 75, and 85 percent of VO2 max. HR was not significantly different at any of the four relative exercise intensities. VE was significantly greater in the obese at 85 percent of maximum only (P less than 0.05) and fb was significantly greater at 55, 75, and 85 percent of maximum. Whereas cardiorespiratory responses of moderately obese women are increased at absolute workloads when compared to that of leaner women, HR is similar at comparable intensities of exercise. VE is also similar at comparable intensities of exercise below ventilatory threshold but fb is greater. The effect of the higher fb on exercise tolerance is unknown.(ABSTRACT TRUNCATED AT 250 WORDS)