Isokinetic Characteristics of the Knee in Female, Professional, and University Ballet and Modern Dancers

Abstract

*Study conducted as part of thesis submitted by R.D.C. in partial fulfillment of the requirements for the degree of Master of Science. The purpose of this investigation was to evaluate isokinetic characteristics of the knee in female, ballet and modern, professional and university dancers in order to evaluate possible differences among the groups. A total of 37 dancers with a mean age of 24.9 years was tested using a Cybex II dynamometer. A multiple analysis of variance (MANOVA) indicated that the ballet dancers had significantly higher H/Q ratios than modern dancers at three speeds (p < 0.024). Post hoc procedures indicated that the professional ballet dancers (PB) had significantly higher H/Q ratios than all other groups at 180 degrees /sec (p < 0.05). Also, although most of these dancers demonstrated normal peak torque/body weight values for knee extension and flexion, specific weaknesses were observed in the force decay rate of the quadriceps curves. It was concluded that these theatrical dancers were not a homogeneous group in terms of certain isokinetic characteristics.J Orthop Sports Phys Ther 1988;9(12):410-418.

Knee and Ankle Strength and Lower Extremity Power in Adolescent Female Ballet Dancers

“…25 The concentric hamstring to quadricep ratio for the ballet group at 60°/sec (0.62) was similar to that reported for university (0.63) and professional (0.69) ballet dancers. 10 However, at 90°/sec the ballet dancers in this study had lower concentric hamstring to quadricep ratios (0.49) than university (0.68) and professional (0.76) ballet dancers. 10 This could indicate an increase in hamstring strength at faster velocities with training, or decreased quadricep dominance with additional years of ballet training beyond adolescence.…”

“…10 However, at 90°/sec the ballet dancers in this study had lower concentric hamstring to quadricep ratios (0.49) than university (0.68) and professional (0.76) ballet dancers. 10 This could indicate an increase in hamstring strength at faster velocities with training, or decreased quadricep dominance with additional years of ballet training beyond adolescence. It may also be due to a protective mechanism resulting in an enhanced co-activation of the hamstrings in the university and professional ballet dancers.…”

“…7,8 In the interest of characterizing the musculoskeletal adaptations of the leg to ballet training, strength comparisons have been made between adult professional dancers and groups of other athletes or sedentary controls. 7,[9][10][11][12][13] However, there is a lack of consensus in the findings both with regard to isokinetic knee flexor and extensor strength 7,9,10,12 and isokinetic strength of the plantar flexors and dorsiflexors. 7,9,11,13 Koutedakis and colleagues have shown that professional ballerinas benefit from supplementary strength training of the quadricep and hamstring muscles, 14 and that decreased thigh strength of dancers is related to increases in injury.…”

The Motor Coordination Reasoning in Acting Dancer's Performance Improvement and Injury Prevention

“…while the dancer is flexing the knees (plié) or in any other situation. In addition to these lesions, associated with lower limb joints misalignments, there are other ones that also affect this important joint, such as anterior cruciate ligaments distension and/or tearing, causing an increase in joint rotational instability and knee hyperextension; and medial collateral ligament distension or tearing, compromising the medial joint stability; patella friction with the trochlear groove, resulting in patellofemoral articular cartilage wear; meniscus lacrimation or rupture; patellar tendinitis and/or chondromalacia increased incidence; jumper's knee; predisposition to patellar displacement and wear [51][52][53][54][55][56][57][58].…”

Isokinetic knee muscular strength is associated with hematologic variables in female modern dancers

“…The isokinetic dynamometer is the gold standard in this kind of evaluation and the test data's collected based on age, gender, and activity level (Stark, et al, 2011). Although there are many studies (Chmelar et al, 1988;Kushner et al, 1990;Westblad, Tsai-Felländer, & Johansson, 1995) concerning the evaluation of isokinetic muscle imbalance in classical ballet dancers, there are lack of studies concerning modern dancers and a lack of consensus on isokinetic muscle profiles (Agopyan et al, 2013;Koutedakis et al, 1997).…”