Facilitating Effects of Fast and Slope Walking on Paraspinal Muscles

OBJECTIVE To quantify the activation of the paraspinalis muscles (multifidus and erector spinae) at different walking velocities and slope with surface electromyography. METHODS This study was a prospective experimental study involving ten healthy male participants. Surface electrodes were placed over the multifidus and erector spinae muscles at the L5 and L3 level. After the electrode was placed at the lumbar paraspinalis muscles, electromyography signals were recorded over 20 seconds. Data were collected three times during the walking exercise at a 0° gradient with the speed from 3 to 6 km/hr. At 7° gradient and 15° gradient, data were also collected three times but a walking speed of 4 km/hr. The area under the curve was calculated for quantitative measurement of muscle activation. RESULTS While the muscle activation was increased at higher walking velocities at the L5 and L3 levels of the multifidus, the erector spinae muscle activation did not show any change at higher walking velocities. At L3 level of the multifidus and erector spine muscles, the muscle activation was significantly increased in 15° gradient compared to those seen in at 0° gradient. At L5 level, the multifidus and erector spinae muscle activation in 0° gradient was not significantly different from that those seen in 7° or 15° gradient. CONCLUSION Fast walking exercise activates lumbar multifidus muscles more than the slow walking exercise. Also, the mid lumbar muscles are comparatively more activated than low lumbar muscles when the walking slope increases.