Análise da cinética de oxigênio e da frequência cardíaca de recuperação após teste de esforço cardiopulmonar em obesas

Abstract

Introduction: Functional capacity is impaired by obesity and can be assessed by physical tests that examine a synchronized action of the cardiovascular, respiratory and musculoskeletal systems. Cardiovascular and respiratory behavior, measured by HR (heart rate) and oxygen kinetics, for example, during the period of exercise recovery has been considered as indicator of cardiovascular health, reestablishment of energy reserves and autonomic balance in healthy and patients with heart disease. However, the behavior of oxygen kinetics and HRR (recovery HR) in obese patients without diagnosed heart disease is not known. Aim: To analyze the pattern of oxygen kinetics and HRR after cardiopulmonary exercise test in obese women. Materials and Methods: a cross-­sectional study with 32 volunteer women, analyzed in the cardiopulmonary exercise test (CPX), allocated for convenience into obesity (GO, N=16) and non-­obese (GNO, N=16) group. We performed a clinical, anthropometric and adiposity and spirometry evaluation. The standard clinical CPX was assessed, (individualized ramp protocol), being done as ventilatory and metabolic measures (breath-­by-­breath), with a recording of interest variables at the rest (2’) and 5 initial (3' active recovery, 2'passive recovery). Oxygen kinetic after exercise was calculated by linear regression model of the decline slope of VO2 over time during the first minute of recovery (T½, VO2/t), and the HRR obtained by the difference between HR at the peak of the test and the HR at the first minute of recovery. Results: groups were homogeneous regarding age, height and spirometric measurements. Significant differences were found in the HRR (p=0,041) and VO2peak (p<0,001) between the groups. The oxygen kinetics presented a significant difference in the T½ of VO2 (p=0,003) and VO2/t (p=0,041). It was observed that VO2peak (0,59), BMI (-­0,16) and HC (0,18) justified the variance of VO2/t in 72%. A negative colinearity between the HC and BMI adiposity measures was attested. Conclusion: young obese has delayed response of VO2 recovery kinetics and HRR regards no obese it suggests that obese has circulatory or reestablishment of energy reserves impairment on peripheral muscles and autonomic dysfunction, and it’s may contribute to the establishment of cardiovascular diseases, and increased morbidity and mortality rate in this population.