Comparative Effects of High-Intensity Interval Training and Moderate-Intensity Continuous Training on Body Fat Percentage among Overweight Adults

Exercise is among the approaches used to manage overweight and obesity, but it has been underutilized. The study’s objective was to compare the effects of high-intensity interval training vs. moderate-intensity continuous training on Body composition. The study used a quasi–experimental design. The study targeted overweight and obese participants at ACK Canon Hesbon Parish of Thika diocese. Stratified allocation was used to place 42 participants in either MICT or HIIT groups. Bioelectrical impedance analysis was used to assess body composition before and after intervention. The training interventions lasted a duration of 12 weeks. Statistical Package for the Social Sciences (SPSS Version 22.0) by International Business Machines Corporation (IBM) was used for data management and analysis. Means, median, and standard deviations (SD) were used to summarise data. The study’s overall mean percentage exercise adherence rate was (M = 61.4836, SD = 15.74183). A paired samples t-test indicated a significant difference between pre-intervention body fat (M =35.1381, SD =6.67781) and post-intervention body fat (M=33.6286, SD=6.73749), t (41) = 11.665, p ≤ 0.000, indicating a general reduction of BF% across both interventions. An independent t-test t (40) = -1.904, p≥ .064 showed no significant difference in BF% changes between HIIT and MICT performance. MICT and HIIT both had an impact on BF% changes. However, HIIT elicited more changes in BF% than MICT, though not statistically significant. The study recommended uptake and further research into a hybrid program that combines features of HIIT and MICT.