Publication date: Available online 12 December 2018
Source: Journal of Biomechanics
Author(s): Junichiro Yamauchi, Keiji Koyama
Abstract
The purpose of this study was to investigate the relationships between the ankle joint angle and maximum isometric force of the toe flexor muscles. Toe flexor strength and electromyography activity of the foot muscles were measured in 12 healthy men at 6 different ankle joint angles with the knee joint at 90 degrees in the sitting position. To measure the maximum isometric force of the toe flexor muscles, subjects exerted maximum force on a toe flexor dynamometer while the activity levels of the intrinsic and extrinsic plantar muscles were measured. The relation between ankle joint angle and maximum isometric force of the toe flexor muscles was determined, and the isometric force exhibited a peak when the ankle joint was at 70-90 degrees on average. From this optimal neutral position, the isometric force gradually decreased and reached its nadir in the plantar flexion position (i.e., 120 degrees). The EMG activity of the abductor hallucis (intrinsic plantar muscle) and peroneus longus (extrinsic plantar muscle) did not differ at any ankle joint angles. The results of this study suggest that the force generation of toe flexor muscles is regulated at the ankle joint and that changes in the length-tension relations of the extrinsic plantar muscle could be a reason for the force-generating capacity at the metatarsophalangeal joint when the ankle joint angle is changed.
from ! Human Diseases via Alexandros G.Sfakianakis on Inoreader https://ift.tt/2C9tWUT
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου