EFFECT OF RUNNING SPEED AND SURFACE INCLINATION ON MUSCLE ACTIVATION DURING TREADMILL RUNNING BY WOMEN

Abstract

The current study examined muscle activity of the biceps femoris (BF), semimembranosus (ST), vastus lateralis (VL), vastus medialis (VM), lateral gastrocnemius (GL), and medial gastrocnemius (GM) during treadmill running. Female college runners (n=15) ran at speeds of 1.79, 2.24, and 2.68 m·s-1 at 3 different grades of incline (0, 10, and 15%). Right leg Muscle activity was assessed via electromyography and normalized to maximal voluntary isometric contraction. Results indicated muscle activity increased with speed and grade except for SM which showed only grades of 0 and 15% being different; and that for GL and SM only 2.68 m·s-1 differed from other speeds. Muscles of the posterior thigh (BF and SM) were different from the posterior shank (GL and GM); while anterior thigh muscles (VL and VM) did not differ from the others. There were no differences in medial/lateral aspects.