Measurement of Fatigue in Isometric Contraction

Abstract

Fatigue in isometric contraction was studied in 30 healthy students (15 males and 15 females) with the mean age of 21.1 ± 3.0 years, the mean height of 164.8 ± 9.7 cm, and the mean body weight of 57.8 ± 10.1 kg.
After exercise, the area under the muscle torque curve, which represents the work load, and the ability of the muscle to produce the maximum torque, decreased with increases in the total number of complaints of subjective symptoms (106) and the frequency of individual complaints. A significant correlation (p < 0.001) was observed between the change in the respiratory function and the reduction in the peak torque or the work load of the muscle. From these results, the decrease in the work load of the muscle is considered to be associated with both the depression of respiratory-circulatory functions and subjective complaints of fatigue.