Background Rhythmic gymnastics (RG) is an Olympic sport that demands high training volume from early age. RG combines elements from ballet, artistic gymnastics and modern dance with manipulation of hand-held apparatus. Most elements require extreme flexibility and strength.

Objective We investigated the extent of, and risk factors for, injuries among competitive Norwegian rhythmic gymnasts.

Design Prospective cohort study.

Setting Norwegian rhythmic gymnasts at national and international level.

Participants One-hundred and seven out of 133 (80.5%) female rhythmic gymnasts participated (mean age: 14.5 years (SD 1.6), mean BMI: 18.9 (SD 2.2)).

Interventions All gymnasts completed a baseline questionnaire and the ’Triad-Specific Self-Report Questionnaire’. Injuries, illnesses and training hours were recorded prospectively for 15 weeks during preseason using the ’Oslo Sports Trauma Research Center Questionnaire on Health Problems’ (OSTRC-H2).

Main Outcome Measurements Prevalence and incidence of injuries (all physical complaints) and illnesses.

Results Gymnasts’ response rate to OSTRC-H2 was 97%. Mean overuse and acute injury prevalence were 37% (95% CI: 36% to 39%) and 5% (95% CI: 4% to 6%), respectively. Incidence was 4.2 overuse injuries (95% CI: 3.6 to 4.9) and 1.0 acute injuries (95% CI: 0.5 to 1.6) per gymnast per year. Overuse injuries in knees, lower back and hip/groin represented the greatest burdens. Previous injury increased the odds of injury (OR 30.38, (95% CI: 5.04 to 183.25)), while increased age (OR 0.61 per year, (95% CI: 0.39 to 0.97)) and presence of menarche (OR: 0.20, (95% CI: 0.06 to 0.71)) reduced the odds of all injuries and substantial injuries, respectively.

Conclusions Overuse injuries were common among Norwegian rhythmic gymnasts. Younger gymnasts had higher all-injury risk. Gymnasts who were not menstruating had higher substantial injury risk. Injury prevention interventions should start at an early age and focus on preventing knee, lower back and hip/groin injuries.