Electromiographic characteristics of the moment of refusal from the work of continuous intensity of athletes-amateurs and persons engaged in physical activities
In the work detailed analysis of the electromyographic curve of the load power of 160 W on a bicycle ergometer with the rotation of pedals at speed of 7 km/h for persons engaged in physical activities and athletes-amateur is made. Characteristic points of control and identification of the peak of activity of muscle, fatigue, and refusal from the work are established. Based on the obtained data and the study of the work of a number of researchers, it was concluded that in individuals engaged in recreational physical activities (non-athletes) at intensive continuous submaximal load, the bioelectrical activity of muscles increases gradually, the peak of its amplitude coincides with the fatigue that began and sets in shortly before refusal from the work. Refusal from the work is connected with the depletion of glycogen in power muscle fibers and is characterized by decrease of the amplitude and impulsation of working motor units. With an instantaneous decrease of load power without reducing the speed of pedaling, the contractile ability of the muscles is recovered. In amateur athletes identical physical activity turns out to be work of great intensity and is characterized by: several peaks of bioelectric activity of muscles, small amplitude and frequency of impulsation of motor units. Fatigue and refusal from the work are connected with vegetative supply disorder and oxygen deprivation of organism with a sufficiently long capability of muscle to maintain the contractile ability with a set power and speed of pedaling.