Endurance times were measured on 12 female subjects for seven different %MVCs and five different shoulder postures. Endurance time decreased nonlinearly with an increase in %MVC. It decresed with an increase in shoulder flexion angle up to 120° and then it increased. This study does not support the recommendation that weights corresponding to 5% of MVC, much less 20% of MVC as suggested by Rohmert, can be held indefinitely.
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