UPPER LIMB MOTION DURING SNOW SHOVELING WITH REGULAR AND MODIFIED SHOVEL

the upper limbs while shoveling. The shoveling was divided into the three phases; squatting, lifting and throwing according to the previous study [2, 3]. The kinematic data during the shoveling were expressed as mean r SD. A Student’s paired t-test was used to determine significant differences between the two types of shovel on measured variables. The p-value was considered significant when it was found to be less than the usual level of significance 0.05. RESULTS AND DISCUSSION Table 1 shows the flexion angles of the elbow joints during the shoveling with the regular and modified shovel. The minimum left elbow flexion angle was significantly smaller in the squatting phase when the subjects used the modified shovel than when they used the regular shovel. Although the maximum left elbow flexion angle was slightly larger when using the modified shovel, there was no significant difference between the two shovels. Moreover, the angular displacement of the left elbow joint was significantly larger when shoveling with the modified shovel. The right elbow flexion angles were significantly smaller both in the squatting and the lifting phases when using the modified shovel. Bending the left elbow would be needed to keep the blade horizontal with the ground so as not to let the snow slip off. Consequently, more stresses may be imposed on the left elbow flexor muscles when using the modified shovel. In order to reduce the amount of the left elbow flexion it may be necessary to increase the lift angle between the blade and the main shaft or to lower the second handle height. Further shovel modification would help users shovel snow more comfortably.