Comparaison of lower limb muscular activity pattern during treadmill and over ground walking in different speeds

The purpose of this study was to evaluate the overall lower limb muscular activity pattern during treadmill walking compared to on the ground walking during stance phase. The study was conducted on 25 healthy female students (19 to 25 years). Surface electromyography was recorded from lateral gastrocnemis, lateral and medial hamstrings, medial and lateral vasti and Gluteus medius muscles. Subjects walked on the ground (along a 6-meter track) at 3 different speeds (slow, fast, and comfortable) and walked on treadmill with matched speeds. The overall pattern of muscle activity including muscle similarity index and magnitude were computed and compared between on the ground and treadmill walking from the heel strike of dominant foot until the heel strike of opposite foot. The main effect of walking conditions (P<0.001) and speed(P<0.001) as well as the interaction effect of walking speed and conditions (P<0.001) on magnitude of muscle activity were significant. The main effect of walking conditions and speed as well as the interaction effect of condition and walking speed were not significant for similarity index. The pattern of muscular activity during walking on treadmil and on the ground was similar but walking on treadmill induced higher muscular activity in the lower limb musculature compared to on the ground walking. The results of this study are useful in assessment and planning of using treadmill in different groups of people considering the induced muscle fatigue and the risk of musculoskeletal injuries.