Objective To evaluate the effectiveness of a junior high school-based sports injury prevention programme to reduce injuries through neuromuscular training (NMT).

Methods This was a cluster randomised controlled trial. Students were recruited from 12 Calgary junior high schools (2014–2017). iSPRINT is a 15 min NMT warm-up including aerobic, agility, strength and balance exercises. Following a workshop, teachers delivered a 12-week iSPRINT NMT (six schools) or a standard-of-practice warm-up (six schools) in physical education classes. The definition of all recorded injuries included injuries that resulted in participants being unable to complete a sport and recreation (S&R) session, lost time from sport and/or seek medical attention. Incidence rate ratios (IRRs) were estimated based on multiple multilevel Poisson regression analyses (adjusting for sex (considering effect modification) and previous injury, offset by S&R participation hours, and school-level and class-level random effects were examined) for intent-to-treat analyses.

Results 1067 students (aged 11–16) were recruited across 12 schools (6 intervention schools (22 classes), 6 control schools (27 classes); 53.7% female, 46.3% male). The iSPRINT programme was protective of all recorded S&R injuries for girls (IRR=0.543, 95% CI 0.295 to 0.998), but not for boys (IRR=0.866, 95% CI 0.425 to 1.766). The iSPRINT programme was also protective of each of lower extremity injuries (IRR=0.357, 95% CI 0.159 to 0.799) and medical attention injuries (IRR=0.289, 95% CI 0.135 to 0.619) for girls, but not for boys (IRR=1.055, 95% CI 0.404 to 2.753 and IRR=0.639, 95% CI 0.266 to 1.532, respectively).

Conclusion The iSPRINT NMT warm-up was effective in preventing each of all recorded injuries, lower extremity injuries and medically treated S&R injuries in female junior high school students.

Trial registration number NCT03312504