Comparison of two heights for forward-placed trunk support with standing work.
Two forward-placed supports with different heights are investigated using human motion capture and EMG. Ten male participants stood in 10 degrees increments of trunk flexion between 0 and 40 degrees for three conditions; leaning on a desk adjusted to the height of the pelvis, leaning on a prototype support at the height of the sternum and with no external support. Low back and hip extensor muscle activity was reduced by an average 60% with leaning against the prototype compared to the no-support condition whereas leaning on a desk produced no significant change in muscle activity. Supported conditions resulted in greater forward displacement of the trunk by at least two-fold compared to no-support representing a longer reach distance. No adverse changes in kinematics indicate that either support blocked segmental flexion of the pelvis, lumbar spine or thoracic spine. These findings suggest that leaning against a higher-placed trunk support could be beneficial for tasks requiring forward flexion.
Damecour
Caroline
C
School of Kinesiology and Health Studies, Queens University, Kingston, Ontario K7L 3N6, Canada. 7cmd2@queensu.ca
Abdoli-Eramaki
Mohammad
M
Ghasempoor
Ahmad
A
Neumann
W Patrick
WP
D000328:Adult; D001696:Biomechanical Phenomena; D004576:Electromyography; D006801:Humans; D017116:Low Back Pain / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D008297:Male; D016273:Occupational Exposure / Q000009:adverse effects / Q000517:prevention & control*; D009864:Ontario / Q000453:epidemiology; D010147:Pain Measurement; D011187:Posture / Q000502:physiology*; D055815:Young Adult