Eftect Of obesitv On Gardio Respiratorv Functions During Exercise In Children

Abstract

Physical activities affect cardiorespiratory functions more than any other form of physiological stresses. Obesity imposes additional stress to ventilation and circulation during exercise as a direct result of the increased body mass requiring greater metabolic energy exchange.

The aim of this work is. to study the effect of obesity on cardiopulmonary function during exercise in obese children.

In our study, obesity was defined as a body weight of >120% predicted weight. No child had a known cause for the obesity or was taking medicines for chronic disease at the time of_study. The protocol consisted of a continoously increasing work rate pattern in which electromagnetically braked cycle ergometer. Subjects began with 4 minutes of cycling at zero watt (unloaded) work rate. The mean 02 uptake during the 4 minutes period was taken as the unloaded cycling. Calibration of our ergometer indicated that the actual work at zero-watt reading was approximately 7 to 10 watts. The work rate was then continuously increased as a constant rate per minute was selected so that the total exercise duration would be more than 6 minutes and less than 14 minutes. The mean time of the test was 9 minutes. The children were instructed to raise a hand when they could not continue, and on this signal the work rate was reduced to zero watt.

Regarding the spirometery results in our study , there were significant differences in FVC and FEV1. The mean values of FVC & FEV1 were higher in obese children.

When FVC & FEV1 were measured as percentage of the predicted value, it seemed that the FVC % AND FEV1 % were reduced in obesity, indicating reduced pulmonary capacity.