Dynamic physiological responses in obese and non-obese adults submitted to cardiopulmonary exercise test

Abstract

Purpose Obese individuals have reduced performance in cardiopulmonary exercise testing (CPET), mainly considering peak values of variables such as oxygen uptake (V˙O2), carbon dioxide production (V˙CO2), tidal volume (Vt), minute ventilation (V˙E) and heart rate (HR). The CPET interpretation and prognostic value can be improved through submaximal ratios analysis of key variables like ΔHR/ΔV˙O2, ΔV˙E/ΔV˙CO2, ΔV˙C/Δlinearized (ln)V˙E and oxygen uptake efficiency slope (OUES). The obesity influence on these responses has not yet been investigated. Our purpose was to evaluate the influence of adulthood obesity on maximal and submaximal physiological responses during CPET, emphasizing the analysis of submaximal dynamic variables. Methods We analyzed 1,594 CPETs of adults (755 obese participants, Body Mass Index ≥ 30 kg/m2) and compared the obtained variables among non-obese (normal weight and overweight) and obese groups (obesity classes I, II and III) through multivariate covariance analyses. Result Obesity influenced the majority of evaluated maximal and submaximal responses with worsened CPET performance. Cardiovascular, metabolic and gas exchange variables were the most influenced by obesity. Other maximal and submaximal responses were altered only in morbidly obese. Only a few cardiovascular and ventilatory variables presented inconsistent results. Additionally, Vtmax, Vt/V˙E, Vt/Inspiratory Capacity, Vt/Forced Vital Capacity, Lowest V˙E/V˙CO2, ΔV˙E/ΔV˙CO2, and the y-intercepts of V˙E/V˙CO2 did not significantly differ regardless of obesity. Conclusion Obesity expressively influences the majority of CPET variables. However, the prognostic values of the main ventilatory efficiency responses remain unchanged. These dynamic responses are not dependent on maximum effort and may be useful in detecting incipient ventilatory disorder. Our results present great practical applicability in identifying exercise limitation, regardless of overweight and obesity.

Obesity and Body Mass Components Influence Exercise Tolerance and the Course of Hypertension in Perimenopausal Women

“…In another study by Gonze et al, the authors analyzed CPETs of 755 obese and 839 non-obese participants. Obese patients achieved the worst results in terms of most of the variables evaluated [ 39 ].…”

The association between variables of cardiopulmonary exercise test and quality of life in patients with chronic Chagas cardiomyopathy (Insights from the PEACH STUDY)

“…Besides that, the high-quality health care provided during the follow-up at a referral center may have positively affected the patients’ perception of QoL. Although the use of beta-blockers does not appear to alter exercise capacity in maximal and submaximal tests, there appears to be a favorable effect on the VE/VCO2 slope [ 65 ]. Thus, as most of our sample was using beta-blockers (93.3%), this may have influenced the CPET response.…”

Cardiorespiratory fitness as a mediator in the relationship between lung function and blood pressure in adults

“…We conducted the CPET on a treadmill (ATL, Inbrasport, Brazil) following a ramp protocol in which increases in speed and inclination were individualized according to the estimated maximum peak oxygen uptake (V̇O 2 ) ( 20 , 21 ). We performed the tests for all participants at the same altitude, atmospheric pressure, and temperature (22°C), and a cardiologist supervised all tests.…”

“…The V̇O 2 was measured breath by breath, and we calculated the average V̇O 2 every 15 s. We considered as maximum effort those tests in which the subject achieved a heart rate at the peak of exercise ≥85% of the predicted value for age (220-age), a gas exchange rate (R) ≥1.0, or a V̇O 2 plateau. The average V̇O 2 of the last 15 s, immediately before the recovery phase, was considered the peak V̇O 2 ( 20 ).…”

“…VO 2 of the last 15 s, immediately before the recovery phase, was considered the peak . VO 2 (20). Accelerometer-based sedentary behavior and physical activity.…”