Effect of Flexion Angle of Knee Joint on Co-contractions of Agonist and Antagonist Muscles
- VernacularTitle:膝关节屈曲角度对主动肌和拮抗肌共同收缩和力矩的影响
- Author:
Qi ZHANG
;
Jiaqi LI
;
Yanwen XU
;
Zhuo ZHANG
;
Kaili ZHOU
- Publication Type:Journal Article
- Keywords:
knee joint angle, agonistic muscle, antagonistic muscle, co-activation, surface electromyography
- From:
Chinese Journal of Rehabilitation Theory and Practice
2007;13(6):581-582
- CountryChina
- Language:Chinese
-
Abstract:
Objective To test the effect of different flexion angles of knee joint on the myoelectric activity and torque of quadriceps femoris and hamstring muscle when these muscles contracting.MethodsElectromyographic activities and isometric torque measurements were performed on 10 healthy subjects at 30°, 60° and 90° of knee joint flexion.ResultsThe results indicated that the greatest maximal voluntary isometric contracture-torque of quadriceps femoris occurred during knee extension at 60° of knee flexion ( P<0.01). However, no significant relationship of maximal voluntary isometric contracture-electromyography and maximal voluntary isometric contracture-torque of quadriceps femoris were found in 10 subjects. But when knee joint was at 90° flexion, hamstring muscle had a greatest neuro-myoelectric activity.ConclusionThe exercise of maximal voluntary isometric contraction of quadriceps femoris and hamstrings muscles at certain knee joint angle can help to maintain the stability of knee joint.
