Endurance limits in different modes of load holding.
This study examines the influence of different modes of load holding on the isometric strength exertion and endurance capacity. Six healthy males underwent longitudinal testing with the trunk, knee and elbow in 10 different (straight and bent) postures. The load heights (LH) of 320, 440, 850 and 1250 mm from the floor level with subject-load-distance (S-L-D) of 120 and 320 mm were used. It was noted that the level and duration of force exertion were higher when the load was placed closer to the body. The endurance times were consistently high with the increase in LH, highest being recorded in Position 9 - i e, with the load placed at the shoulder level and S-L-D of 120 mm. As evident from MVC and endurance times, the back straight/knee bent postures may not be preferred to back bent postures.
Nag
P K
PK
Occupational Physiology Division, National Institute of Occupational Health (Indian Council of Medical Research), Ahmedabad 380 016, India.