Estudio de la actividad muscular durante el relevé en primera y sexta posición

Abstract

Background To determine differences in muscular activation during relevé. Participants and method Eighteen classical dancers (aged 14-32 years) participated in this study. Kinetic and cinematic analysis was performed. The degree of plantar flexion achieved and the involvement of distinct muscles were analyzed. The results obtained were compared (Wilcoxon's test) on executing relevé in sixth position ( en parallel) and in correct first position ( en déhors) with respect to first position with foot pronation. Results A greater range of plantar flexion was achieved in sixth position than in first position, and in correct first position than in pronated first position. The internal gemellus muscle showed greater activity in first position; the abductor muscle of big toe (ABT) en parallel or sixth position and the peroneal muscles and external gemellus muscle in pronated first position. The lateral peroneal muscle showed differences during relevé (in static initial position and the rising phase) and the ABT during the rise to relevé. The internal gemellus muscle showed earlier and slower activation than the external gemellus muscle in plantar flexion during relevé. Discussion The ABT shows greater activity when the hips are en parallel than when they are turned out ( en dehors). The lower activity of the ABT in first position ( en dehors) may lead to a lack of stability in the longitudinal arch and first ray and consequently to a greater risk of injury. Relevé in sixth position allows greater plantar flexion than that in first position. Pronation of the foot – due to faulty technique – allows less plantar flexion. The differences found in muscular activity of the lateral peroneal muscle are related to the presence of foot pronation, with pronation producing greater activity.