Introduction: The increasing rates of adolescent overweight and obesity are adversely impacting their physical performance. Also, high-intensity interval training (HIIT) and high-intensity functional training (HIFT) are popular methods to improve functional capacity and weight management. Therefore, this study aimed to assess the effects of six weeks of HIFT versus HIIT protocols on anthropometric measures and functional capacity of overweight and obese adolescent boys.
Method: In this randomized controlled trial, thirty adolescent boys aged ۱۳-۱۵ years, classified as overweight or obese (Body Mass Index (BMI) >۲۵ kg/m۲), were randomly and equally assigned to three groups: control, HIIT, and HIFT. Physical fitness indices (agility and VO۲max), functional movement screen (FMS), and anthropometric measures (weight, BMI, and Waist-to-Hip Ratio (WHR)), were assessed. The experimental groups followed either the HIIT or HIFT protocols for six weeks. To analyze data a ۲ (Time) x ۳ (Group) mixed-model of repeated measures ANOVA was used.
Results: The demographic characteristics of study population include age =۱۳.۹۳±۰.۸۲ (years), weight= ۸۸.۸۶±۱۳.۰۷ (Kg) and BMI=۲۹.۶۰±۲.۳۶ (Kg/m۲). Data were showed that there were not any significant differences between groups for age (p=۰.۲۵۶), height (p=۰.۲۱۸) weight (p=۰.۳۰۸) and BMI (p=۰.۵۹۲) in base line. The results showed that both HIIT and HIFT protocols had a significant effect on physical fitness indices, FMS, and BMI (all, p ≤ ۰.۰۵). However, the HIFT protocol demonstrated a greater effect compared to HIIT and was significant in all variables (except agility) compared to the control group (p ≤ ۰.۰۵). Despite the lack of a significant difference in post-test weight, the HIFT protocol showed a significant difference compared to the control group (p ≤ ۰.۰۵).
Conclusion: Six weeks of HIIT and HIFT protocols improved the functional capacity and BMI of overweight and obese adolescents. But it appears that the HIFT protocol has a greater effect on the functional capacity, possibly due to the improved muscle strength and endurance, and weight loss.