Impact of Aerobic and Resistance Exercise Training on Body Composition and Functional Fitness among Obese Young Adults: A Comparative Study

Abstract

Background: Obesity among young adults in South Asia is a growing public health concern, exacerbating cardiometabolic risks and impairing functional fitness, yet comparative studies on exercise modalities in this population are sparse. Objective: This study aimed to compare the effects of 12-week aerobic versus resistance exercise training on body composition (body fat percentage, muscle mass, BMI, waist-hip ratio) and functional fitness (6-minute walk test distance, step test heart rate recovery) in obese young adults. Methods: Sixty obese adults (aged 18-30 years, BMI 30-40 kg/m²) were randomly allocated to aerobic (moderate-intensity treadmill/cycling, n=30) or resistance (progressive overload training, n=30) groups in Lahore, Pakistan, from March 2023 to September 2024. Body composition was assessed via bioelectrical impedance, and functional fitness via standardized tests. Repeated measures ANOVA with Bonferroni post-hoc tests analyzed within- and between-group differences, adjusting for age, sex, and caloric intake. Results: Aerobic training significantly reduced body fat percentage (-11.2%, p<0.001) and BMI (-6.2%, p<0.001), and improved 6MWT distance (+14.6%, p<0.001) compared to resistance training (-6.7%, -3.5%, +7.4%, respectively; between-group p<0.05). Resistance training increased muscle mass (+8.8%, p<0.001) versus aerobic (+2.1%, p=0.12). Conclusion: Aerobic training excels in fat reduction and endurance, while resistance training enhances muscle mass, suggesting combined modalities for optimal obesity management.