Análise discreta e funcional da assimetria bilateral de produção de torque de ciclistas amadores em diferentes intensidades e momentos de exercício

Abstract

In cycling, applying torque to the pedals, positioning the rider on the bike, and peak power appear to directly affect performance. Cyclists use different strategies to maintain performance, such as decreased pedaling cadence, modification of muscle activation and torque production asymmetry. It is also important to consider that cyclists are subjected to submaximal intensities for long periods and during these lower intensities higher levels of torque production asymmetry are expected. In addition, the fatigue process that occurs during exercise can cause changes in the level of bilateral asymmetry. Therefore, the objective of the present study was to verify the effect of different workloads and moments (beginning and end) of exercise on the asymmetry behavior through two analyzes, a discrete analysis from the peak torque and a functional analysis, considering all pedaling cycle. The sample of this study consisted of amateur cyclists who underwent a test to determine the maximum pedaling power and three tests with power (60, 80 and 95% powerMAX) and fixed cadence until exhaustion with 48h interval between each session. To verify the behavior of bilateral asymmetry between workloads through peak torque, a two-way repeated measures ANOVA was used, and the analyzed factors were workloads (60, 80 and 95% powerMAX) limbs (right and left). To verify the behavior of bilateral asymmetry between different exercise moments, a two-way ANOVA was also performed with the factors moments (beginning and end) and limbs (right and left). To determine asymmetries in time series, a two-way functional variance analysis (FANOVA) for repeated measures was applied, considering the same factors included in the ANOVA approaches. In all analyzes, a significance level of 5% was adopted. The discrete analysis showed no differences between the members regardless of the exercise intensity analyzed, however, the functional analysis showed some differences between the members within the cycle between the right and left members, information that the discrete analysis disregards since it only uses the peak torque variable. Regarding the timing of the exercise, there were no significant differences between the members regardless of the method of analysis used or the exercise intensity. The results of the present study confirmed the hypothesis that FANOVA would be more sensitive in detecting asymmetry in the torque production profile in amateur cyclists compared to ANOVA. However, the hypotheses that the increase in intensity and the moment of exercise influenced the asymmetry behavior were not confirmed.