Background: Physical exercise is an integral part of pulmonary rehabilitation programs. The present study was conducted to evaluate the impact of moderate and high intensity exercise on lung volumes, lung capacities, and breath holding time. Materials & Methods: 80 healthy subjects of both genders were divided into 2 groups of 40 each. Group I subjects performed moderate-intensity continuous exercise and group II subjects performed high-intensity exercise. Pulmonary functions were recorded using a computerized spirometer. The values of VC, TV, IRV, and ERV were noted. Results: The mean age in group I was 34.6 years and in group II was 35.2 years, weight was 60.2 Kgs and 58.8 Kgs, height was 172 cm in group I and 170.4 in group II and waist- hip ratio was 0.97 in group I and 0.86 in group II. The mean change in TV (litres) was 0.02 and 0.03, IRV (litres) was 0.26 and 0.37, IC (litres) was 0.70 and 0.42, VC (litres) was 0.36 and 0.58, ER (litres) was 0.08 and 0.21, EC (litres) was 0.12 and 0.20 and BHT (Seconds) was 1.42 and 4.38 in group I and II respectively. There was a positive correlation of all three parameters with BHT but it was not significant. The correlation of BHT with IC was strongest, whereas that with VC was weakest. Conclusion: There was improvement in VC, IC, EC, and BHT after exercise training sessions in both the moderate intensity and high-intensity exercise groups. Key words: Exercise, Lung volumes, intensity activity