The capability of children and adults to activate the quadriceps femoris during the isometric workload Keywords: voluntary strength, involuntary strength, electro stimulation, muscles. Summary. In everyday activities human organism confronts different changes of characteristics of the muscle that can have impact on the efficiency of human work. There have been quite a few studies where during maximal voluntary strength single impulse stimulation was applied to the quadriceps femoris. The applications of single impulse twitch have lead to the suggestion that healthy human subjects could fully activate most of the skeletal muscles to which the technique had been applied. However, more recently twitch interpolation has revealed that even healthy adults routinely fail to fully activate a number of skeletal muscles despite apparently maximal effort. The observations have lead to the suggestion that the single interpolated electric impulse into the muscle can not accurately estimate voluntary activation. The purpose of the study. To determine and compare the capability to activate the quadriceps femoris muscle during the isometric workload in children and adults. The objectives of the study. 1. To determine children’s voluntary and involuntary strength of the quadriceps femoris muscle. 2. To determine adults’ voluntary and involuntary strength of the quadriceps femoris muscle. 3. To compare the activation of children and adults’ voluntary and involuntary strength of... [to full text]