In the present study, the fascicle length (L(fa)) of the human medial gastrocnemius (MG) muscle was monitored to evaluate possible input from the short-latency stretch reflex (SLR) during the stance phase of running and to examine its timing at various running speeds. Eight subjects ran at 2.0, 3.5, 5.0, and 6.5 m/s. The L(fa) was measured with the high-speed ultrasound fascicle scanning togeth...

The oxygen cost and energy expenditure of submaximal treadmill running was evaluated in 9 male distance runners. The oxygen consumption--running speed relationship was highly significant (r = .917) and linear over the entire aerobic range. The caloric cost of 0.97 Kcal/kg/k was in close agreement with values found in the literature and was independent of running speed. The caloric cost per unit...