Evaluation of passive plantarflexion torque and active dorsiflexion torque in rhythmic gymnasts and nonathletes

Abstract

The training performed by elite athletes leads to specific functional demands, producing changes on tendon and muscle properties. In the rhythmic gymnastics (RG) athletes there is a higher motor control demand in extreme plantarflexed positions. This functional demand can change the passive torque produced by the plantarflexors, as well as influence the dorsiflexion range of motion (ROM) and maximal dorsiflexion torque. We compared the dorsiflexor ROM and the influence of the passive plantarflexion torque (PPT) on the active dorsiflexion torque (ADT) between RG and nonathletes (NA) girls. The study included 10 RG and 10 NA. The dorsiflexor ROM was measured with a goniometer. The PPT and ADT were evaluated through isokinetic dynamometry at five ankle joint angles (20º, 10º, 0º, -10º, -20º). Independent T test was used to comparison between groups (α = 0.05). Pearson correlation coefficients indicated a high and moderate negative correlation between PPT and ADT for RG and NA, respectively. RG had a smaller dorsiflexion ROM than NA. The PPT was significantly higher in RG compared NA. In contrast, the ADT was higher in NA. The PPT correlation to ADT was r = -0.82; p < 0.01 and r = -0.68; p < 0.01, for RG and NA, respectively. Results suggest that higher mechanical loading on plantarflexors in the RG increase the PPT that influence negatively in the dorsiflexor ROM and ADT.