Two-dimension single-muscular stress variation and muscle function of lower-limb in the integral gait of sprint running

For quantifying the variations in lower-limb monoliphic muscles stress in sprint running and analysing its influence on sprint running, in this study eight excellent sprinters´ two-dimensional kinetic data, the data of the ground´s counterforce and the electromyography signal are collected concurrently and the variations in lower-limb monoliphic muscles stress is optimized. Results reveal in sprint running the variation of lower-limb redundant muscle strength is similar to the full-wave rectification of EMG. During the support phase, a higher level of stress emerges in such muscles as GM, HAM, SOL and GAS. During the earlier stage of swing phase, it is mainly such muscles as IL, VAS, RF, BFsh and GAS that do work. During the later period of swing phase, only HAM and GM are active. During every phase the stress peak value of such two-joint muscles as HAM, RF and GAS is strikingly higher than tthat of the other muscles.