Effects of aerobic endurance, muscle strength, and motor control exercise on physical fitness and musculoskeletal injury rate in preprofessional dancers: an uncontrolled trial.

OBJECTIVE

The purpose of this study was to evaluate musculoskeletal injury rate and physical fitness before and 6 months after an endurance, strength, and motor control exercise program in preprofessional dancers.

METHODS

This uncontrolled trial was completed at a college offering a professional bachelor degree in dance. Forty preprofessional dancers underwent a test battery before and after a 6-month lasting exercise program in addition to their regular dance lessons. Physical fitness was evaluated by means of a submaximal exercise test with continuous physiological monitoring and by a field test for explosive strength. Anthropometric measurements were taken to analyze the influence of fitness training on body composition. Musculoskeletal injury incidence and quality of life were recorded during the 6-month lasting intervention. An intention-to-treat analysis ("last observation carried forward" method) was used with a Student t test for normally distributed variables. The Wilcoxon signed rank and Mann-Whitney U tests were used as nonparametric tests.

RESULTS

Physical fitness improved after the 6 months of additional training program (P<.05). The waist:hip ratio (P=.036) and the sum of the measured subcutaneous skin thickness (P=.001) significantly decreased. Twelve dancers developed musculoskeletal complaints, requiring temporary interruption of dancing.

CONCLUSIONS

The combination of regular dance lessons with an additional exercise program resulted in improved physical fitness in preprofessional dancers, without affecting the aesthetical appearance. A relatively high injury rate was observed during the intervention period. These results suggest that a randomized, controlled trial should be performed to examine the effectiveness of additional exercise in dancers on physical fitness and musculoskeletal injury rate.