The effect of reach levels, horizontal angles and vertical angles on isometric pull and push strengths of males and females in standing and seated positions was determined. The effect of reach levels on strength varied as a consequence of force direction, working position and gender. Reach level has a significant effect on women's pull strength in the seated position and on push strength in the standing position. The strength value was significantly greater in the extreme reach than in maximum or normal reach. Vertical angle ö had a significant effect on strength consistently in all cases. Strength values increased significantly with the increase of ö angles from 0º to 45º to 90º. The horizontal angle è had a significant influence only on the pull strength of standing and seated men and standing women (not seated woman). The maximum strength was significantly greater at è = 90º.
The isometric pull and push strength profiles of males and females were determined in seated and standing positions in the workspace. The strongest pull strength location was at extreme reach vertically above the shoulder for both males and females. The greatest pull strength of 400 Newtons (N) for males was recorded in the seated and standing positions. Females. pull strengths in the seated and standing positions were 222 and 244 N, respectively. The strongest push strength was always at the maximum reach at the overhead location. Males. maximum push strength was 227 N in the seated position and 251 N in the standing position. Females’ maximum push strength was 96 N in the seated position and 140 N in the standing position. On the average the strength in the standing position was 79% of the seated position. The push strength was 71% of the pull strength and females were 56% as strong as males.
The isometric strength profiles of male and female paraplegics were determined for pull and push strengths in the normal, maximum, and extreme working reach envelopes. A computerized isometric strength measurement system was designed and constructed for the purpose. The strongest pull location was at extreme reach vertically above the shoulder and the strength values for males and females were 473 and 318 newtons (N), respectively. The strongest push location was at maximum reach, at vertical ($) angle of 45° and at horizontal (6) angle of 45° for males and at 0° for women and the strength values were 235 and 172 N, respectively. The nature of the strength profiles was found to be similar for both the sexes. The pull and push strengths of the female were 77 and 68% that of the male, respectively.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.