Effect of Menstrual Cycle on Neuromuscular Efficiency and Muscular Strength in Runners

Abstract

PURPOSE: The aim of this study was to examine the influence of the menstrual cycle (MC) stages on neuromuscular efficiency and muscular strength in female runners. METHODS: Three runners (females) underwent testing using a BIODEX isokinetic dynamometer concurrently with a BioPac EMG, during which peak torque, peak torque/body weight, time to peak torque, mean amplitude, median amplitude, minimum amplitude, maximum amplitude, frequency, and the p-p value were collected throughout the test. During the test, the performance variables were assessed on the quadriceps (rectus femoris) muscle and collected at speeds of 60 degrees/second and 180 degrees/second. STATISTICAL ANALYSIS: A paired-sample t-test was used to determine the correlation between neuromuscular efficiency and peak torque of the quadriceps during extension in the two MC phases. A paired-sample t-test was also used to determine the difference in neuromuscular efficiency between the MC phases, as well as peak torque between the MC phases. RESULTS: Muscular strength testing did not reveal statistical significance between neuromuscular efficiency and peak torque of the quadriceps during MC phases. Furthermore, there was no statistical significance between the differences in peak torque of the MC phases. Maximum amplitude at 60 degrees/second on the left leg between the MC phases revealed statistical significance (p = 0.026). EMG wave frequency at 60 degrees/second on the right leg between the MC phases revealed statistical significance (p = 0.007). CONCLUSION: Results show a significant difference in maximum amplitude and wave frequency at 60 degrees/second during knee extension between the MC phases.