title: Thigh-muscles strength training, dance exercise, dynamometry, and anthropometry in professional ballerinas.
abstract: The purpose of the present study was to assess the effects of 12 weeks of quadriceps and hamstring strength training on torque levels after a dance exercise and on selected anthropometric parameters. The sample consisted of 22 (ages, 25 +/- 1.3 years) full-time professional ballerinas who were randomly assigned into experimental (n = 12) and control (n = 10) groups. A dance routine designed to cause fatigue within 5 minutes, isokinetic dynamometry, and anthropometric assessments were conducted before and after strength training in both groups. Before strength training, the dance routine resulted in significant reductions of hamstring (p < 0.001) and quadriceps (p < 0.001) peak torques in both subject groups. However, after strength training, only control subjects demonstrated such torque decrements (p < 0.001) after the dance routine. Furthermore, the experimental group revealed greater knee extension (119 vs. 138 N.m; p < 0.001) and flexion (60 vs. 69 N.m; p < 0.001) torques, smaller sum of skinfolds (33.6 vs. 27.8 mm; p < 0.01), more fat-free mass (37.7 vs. 39.4 kg; p < 0.05), but unchanged body mass (p > 0.05) and thigh circumferences (p > 0.05). A negative relationship (p < 0.001) was found between initial strength levels and improvements measured at the end of the 12-week program. These results suggest that supplementary strength training for hamstring and quadriceps muscles is beneficial to professional ballerinas and their dancing; weaker individuals are more likely to benefit from such regimens than their stronger counterparts, whereas increases in thigh-muscle strength do not alter selected aesthetic components.
authors.affiliation: School of Sport, Performing Arts, and Leisure, University of Wolverhampton, West Midlands, United Kingdom. y.koutedakis@uth.gr
authors.forename: Yiannis
authors.initials: Y
authors.lastname: Koutedakis
authors.forename: N C Craig
authors.initials: NC
authors.lastname: Sharp
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D000886:Anthropometry; D001696:Biomechanical Phenomena; D003615:Dancing / Q000502:physiology*; D005260:Female; D006801:Humans; D018482:Muscle, Skeletal / Q000502:physiology*; D010806:Physical Education and Training / Q000379:methods*; D013848:Thigh / Q000502:physiology*; D019415:Torque