Analysis of Heart Rate Recovery and Oxygen Kinetics After Cardiopulmonary Exercise Test in Obese Women
obesity, oxygen uptake, heart rate, cardiopulmonary exercise test.
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 an 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 behavior of HRR and oxygen kinetics after cardiopulmonary exercise test in obese women. Materials and Methods: a cross-sectional study with 14 volunteer obese women, analyzed in the cardiopulmonary exercise test (CPX), allocated for convenience into obesity (GO, N=7) and non-obese (GNO, N=7) group. We performed a clinical, anthropometric and adiposity and spirometry evaluation. The standard clinical CPX was assessed on a different day, using individualized ramp protocol, being done as ventilatory and metabolic measures (breath-by-breath), with a recording of variables during a period of 2 minutes in pre-test rest and 5 minutes (3' active recovery, 2'passive recovery). Oxygen kinetic after exercise was calculated by linear regression model considering the first decline slope of VO2 during the first minute of recovery (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. SPSS 20.0 software was used to analyze a difference between the GO and GNO groups, and the unpaired t test, and measures of association between variables. Preliminary Results: The age and spirometric measures of the participants of both groups were homogeneous. The GO had VO2peak (20.21 ± 1.45) and no LV1 (ventilatory threshold) (15.71 ± 1.09) lower than the GNP (32.31 ± 5.6 and 21.34 ± 2.91). The GO showed slowing in the FCR1' (p <0.005), and in O2 kinetics than the GNO (p <0.001). Conclusion: The data point to a tendency of obesity, even without diagnosed heart disease, to present an oxygen kinetics and a slower HRR.