CALCULATION OF METABOLIC POWER IN LEVEL SURFACE RUNNING USING THE JOINT POWER METHOD

This paper outlines results of the calculation of metabolic power in level surface running. We use a method initially mentioned by Elftman (1 940), later used by Cappouo et al. (1976), and stated in the final form in 1986 by Aleshinsky. A full threedimensional study was done using the Hanavan model. For the animation on computer we used the SDS animation system. The joints (where muscles contribute the most power during running) are identified and the power contributions are shown as functions of time. In this study 11 sport students (1 0 male, 1 female) participated. We measured their anthropometry and used it to establish the individual Hanavan models. The first group of seven male students performed on an outdoor track. They ran once with a maxi- mum speed of (7.8 - 8.9 m / ~)an d once at a slower pace (4 - 5 rnls). A second group of 4 students (3 male and 1 female) performed indoors. Each of them ran four times: one run at a pace of approximately 4 m/s, one at approximately 6 m/s, and two runs at a speed between 7.7 m/s and 8.7 mls. All of them were filmed using 3 video cameras (PAL 50 Hz) synchronously. Digitizing was done manually using the Peak Performance system. The data output showed the coordinates of 18 points for the first group (ears, shoulders, elbows, wrists, fingers, hips, knees, ankles, toes), and 16 points for the second group (fingers omitted). We con-verted and calculated these parameters and supplied the SDS animation and simulation system with the necessary coordinates, velocities, and accelerations. One result demonstrates that at least 75% of the metabolic power is generated by muscles causing the torque at the joints in the lower extremities including the hip joints. The follow-ing figure displays the total power and the power of the main contributing joints, the hip and the knee joints