Analysis of Kimematics And Electromyography of Cyclists In the Length of Handling: 239 Board #77 May 29 11:00 AM - 12:30 PM

PURPOSE: The cyclist's accommodation on the bicycle is essential to avoid injuries and improve performance. The adjustment of the handlebar range of the bicycle can have similar or contrary effects to the horizontal adjustment of the saddle. The backward position generates pelvic anteversion, decreased hip angle, greater activation of the hamstring muscles, plantar flexors and greater tibio-femoral shearing force. On the other hand, the forward position of the saddle generates retroversion of the hip, increase in the angle of the knee, decrease in the activation of the hamstrings and increase of the strength in the quadriceps and can generate patello-femoral pain. PROPOSITION: Evaluate the variations in muscular activity and joint ranges of the lower extremities in the cycle of pedaling, by changing the length of the handlebar reach in amateur cyclists METHODS: Eight male cyclists (Age: 41.75 ± 10.08 years; Weight: 72.56 ±5.53 Kg) of right predominance were measured. The hip, knee and ankle joint angles (three-dimensional kinematics) and muscle activity of the Biceps Femoral, Lateral Gastrocnemius, Lateral and Medial muscles (surface electromyography) and the adjustment of their bicycles in three handlebar lengths were recorded: a) preferred. b) advanced (preferred + 3 centimeters) and c) delayed (preferred - 3 centimeters). It was carried out two stress tests one of incremental load of maximum power and another of constant load to 57% of the maximum power at 90 rpm RESULTS: A variance analysis (ANOVA) finding differences in the activation units of the left lateral gastrocnemius muscle in the preferred position vs. back (0.34 vs. 0.18, p = 0.042) and between the position of the left hip at 150 ° between the forward vs. back position (96.64 vs. 101.20, P = 0.05). CONCLUSIONS: The modification of the handlebar ranges of the bicycle from the preferred position to the backward one, produces an increase in the angle of the hip generating pelvic anteversion. This variation is presented at 150 degrees of the cycle of pedaling in the transition from maximum power to that of the bottom dead center, with the decrease in the activation of the left lateral gastrocnemius muscle.