Effect of basketball-based small-sided games and running-based high-intensity interval training on physical fitness in untrained young adults: a randomized controlled study

Objective To investigate the differences in the effects of basketball small-sided games (SSG) and running-based high-intensity interval training (HIIT) on body composition and exercise performance-related physical fitness in untrained young adults.Methods A randomized controlled trial design was adopted, with outcome assessors blinded. Ninety untrained participants (aged 19.83 ± 0.70 years, including 45 females) were randomized to the basketball SSG group, HIIT group, and control group in a 1:1:1 ratio (30 participants per group). One participant in the HIIT group discontinued the intervention, and 89 participants were included in the final analysis. The basketball SSG group and HIIT group trained 3 times a week for 8 weeks; the control group did not receive any structured training.Results Intra-group analysis showed that after 8 weeks of intervention, both training methods significantly improved core indicators (all p  .05). Inter-group comparison revealed that the two intervention groups had significant differences compared with the control group in 10-meter sprint (SSG group: MD=-0.226 s, 95%CI: -0.366 to -0.086; HIIT group: MD=-0.183 s, 95%CI: -0.324 to -0.041), 30-meter sprint (SSG group: MD=-0.326 s, 95%CI: -0.608 to -0.044; HIIT group: MD=-0.444 s, 95%CI: -0.729 to -0.159), COD (SSG group: MD = - 0.153 s, 95% CI: -0.296 to - 0.010; HIIT group: MD = - 0.172 s, 95% CI: -0.316 to - 0.028), and aerobic endurance (SSG group: MD = 90.000 m, 95%CI: 5.676 to 174.324; HIIT group: MD = 104.345 m, 95%CI: 19.297 to 189.393) (all p  .05).Conclusion This study indicates that both 8-week basketball-based SSG and HIIT interventions can effectively improve body composition and several physical fitness outcomes in untrained young adults compared with no structured training. However, no significant differences were observed between the two intervention groups across the assessed outcomes. These findings suggest that both approaches may be considered feasible exercise options for improving physical fitness in sedentary young adults.Trial registration ISRCTN14130863, registered 12. February 2026, retrospectively registered.