Mechanical and electrical behavior of human muscle during maximal concentric and eccentric contractions

Abstract

The force-velocity relationships of human muscle (e.g., Asmussen, Hansen, and Lammert, 1965; Komi, 1973a) characterize the main mechanical differences in concentric and eccentric work. Some information also has been reported on the interrelationship between neural input and mechanical output during submaximal concentric and eccentric contractions. The slope of the regression line representing the relationship between IEMG and muscle tension is greater when muscle shortens at a constant velocity than when it lengthens at the same velocity (Bigland and Lippold, 1954). When recordings were made with a greater number of velocities, then a family of curves was obtained, a result which emphasizes the importance of the contraction velocity in determining the pattern of IEMG-muscle tension (kg) relationship (Komi, 1973b).