Background: In healthy teenagers, obesity and physical inactivity are the two main factors that affect respiratory function. The aim of this study was to evaluate the effect of aerobic exercise training on improving lung function in overweight and obese students.
Materials and methods: Thirty overweight or obese subjects with poor endurance performance and mild deterioration of respiratory indices (forced expiratory volume and forced expiratory volume in 1 second < 90% predicted) were randomly assigned into control (age: 16.6±0.83 years, height: 167±5.05 cm, weight: 80.44±7.65 kg) and intervention groups (age: 16.5±0.83 years, height: 166±6.7 cm, weight: 79.62±9.33 kg). The intervention group preformed 24 weeks of continuous treadmill running (3 days a week). Respiratory indices were measured pre, mid and post exercise. Independent t test, paired t test, Pearson's correlation test and repeated measure were used for analyzing the data.
Results: In the intervention group, post exercise respiratory indices were significantly higher than the pre exercise values, and did not reach the predicted values. No significant differences were found in pre, mid and post exercise respiratory indices in the control group. In the intervention group, improvements in respiratory indices were positively correlated with maximum voluntary ventilation (MVV) improvement but not with BMI reduction. No significant differences were detected between the 2 groups in terms of pre, mid and post exercise measures of BMI, weight, height, and respiratory indices.
Conclusion: In overweight and obese teenagers, appropriate aerobic exercise training can partly improve lung function by strengthening the muscles of respiration. However, in order to achieve the predicted values of lung function, a further increase in activity duration and decrease in BMI is necessary.
Keywords: Aerobic exercise; BMI; Continuous treadmill running; FEV1; FVC; MVV; Overweight teenagers.