Multimodal high-intensity interval training elicits greater improvements in aerobic capacity and sprint performance versus small-sided games and drill-based HIIT in adolescent basketball players: a randomized controlled trial

Traditional high-intensity interval training (HIIT) often lacks sport specificity, while small-sided games (SSG) may fail to isolate specific physiological qualities. Integrating both approaches could optimize training efficiency. Therefore, this study aimed to compare the effects of a multimodal HIIT (M-HIIT) protocol versus conventional small-sided games (SSG) and drill-based HIIT (DB-HIIT) on pre-specified primary outcomes (aerobic capacity, 20-m sprint performance, defensive agility, and perceived training loads) and secondary outcomes (repeated-sprint ability, anaerobic capacity, vertical jump, ball control, and shooting) in adolescent basketball players. Thirty-six male adolescent players (mean age: 14.8 years) were randomly assigned to M-HIIT, SSG, or DB-HIIT groups. Throughout the intervention, perceived training loads and internal training load (ITL) were continuously monitored to compare the acute perceptual demands of each protocol. Following a 6-week intervention (12 sessions, twice weekly), 30 participants completed pre- and post-assessments of aerobic capacity (Yo-Yo IR1), sprint performance (10/20 m), repeated-sprint ability (RSA), agility (T-test, line drill), vertical jump (CMJ), and technical skills (shooting, ball control). Between-group differences were analyzed using analysis of covariance (AN-COVA) with baseline values as covariates. For primary outcomes, the M-HIIT group demonstrated the largest improvements in estimated VO₂max (+ 10.9%, d = 2.33), 20-m sprint time (-5.1%, d = -1.92), and RSA fatigue resistance (decrement score: -7.39 points, d = -2.66). Between-group analyses confirmed that M-HIIT induced significantly greater gains in aerobic capacity, linear sprint performance, and fatigue resistance compared with both SSG ( p < 0.05) and DB-HIIT ( p < 0.01). Defensive agility (a primary outcome) improvements favored M-HIIT over DB-HIIT ( p = 0.007) but were comparable to SSG. Regarding secondary outcomes, M-HIIT induced greater improvements in repeated-sprint fatigue resistance and anaerobic capacity compared to both SSG and DB-HIIT, whereas ball control and shooting performance improved similarly across all groups. M-HIIT is a time-efficient conditioning strategy that elicits enhanced aerobic, sprint, and fatigue-resistance adaptations compared with conventional SSG or DB-HIIT, without compromising technical skill development. Coaches should consider integrating multimodal formats into youth basketball train-ing to simultaneously optimize physiological and sport-specific outcomes.