Musculoskeletal Injuries, Pelvic Floor Dysfunctions and Menstrual Irregularities in Norwegian Rhythmic Gymnasts and Dancers - Observational and Cluster Randomized Controlled Studies

BACKGROUND

Norwegian rhythmic gymnasts have high prevalence and incidence of overuse injuries. Previous research on risk factors related to injuries in rhythmic gymnastics (RG) has implied that high weekly training load, hypermobility, poor technic and inappropriate training load increase the risk of injuries. A prospective study also found that previous injury increased the risk of injuries substantially (Gram, M., Clarsen, B., & Bø, K., 2021). Hence, injury prevention interventions should start at an early age to avoid the first injury. In addition, since the aetiology and mechanisms of injuries are multifactorial, with a well described complex interaction of internal and external risk factors making a gymnast more or less prone to sustain an injury, there might be a need to assess some internal risk factors more thoroughly. The modifiable internal risk factor physical capacity, e.g. strength, flexibility, stability, might be of particular interest, since lack of physical capacity can be thought of as a potential underlying cause in all of the above-mentioned risk factors. In addition, it is well known how persistent lack of physical capacity relative to the requirements in a sport might lead to injuries. With knees, lower back and hip/groin as the most commonly reported injury locations, clinical assessment of strength, flexibility and stability in these locations has been conducted in a cross-sectional study before this randomized controlled trial (RCT). Reduced physical capacity revealed in the cross-sectional study will be targeted/brought forward in the exercise program in the RCT.

The most common types of pelvic floor dysfunctions (PFD) are urinary incontinence (UI), anal incontinence (AI) and pelvic organ prolapse (POP). UI has high prevalence among female athletes participating in sports including jumping and running (high impact). A prevalence of 80% was found in young, nulliparous high-level trampoline jumpers in Sweden (Eliasson et.al., 2008). The prevalence among Norwegian rhythmic gymnasts was >30%, while Thyssen et.al. found that 56% of female Danish artistic gymnasts and 43% of dancers reported UI. UI negatively affects sports performance, and symptoms at young age is a risk factor of future UI developing during pregnancy and after childbirth. Hence, interventions toward prevention and treatment is necessary. While strength training of the pelvic floor muscles has 1A level of evidence/recommendation to treat UI in the general female population, and has no known adverse effects, there is little knowledge of this among young female athletes and dancers. Search on PubMed revealed only one RCT assessing the effect of pelvic floor muscle training on UI in female athletes. Ferreira et.al. randomized 32 female volleyball players to 3 months of pelvic floor muscle training or control, and found statistically significant improvement in the exercise group in frequency of leakage and urine loss measured during physical activity(p< 0.001). Hence, there seem to be a potential for prevention and treatment also in athletes exposed to heavy load towards the pelvic floor.

AIMS

The aims of this RCT are to investigate if implementation of prophylactic exercises targeting reduced capacity and pelvic floor dysfunction can prevent/lower the prevalence of overuse injuries and UI among Norwegian rhythmic gymnasts.