Resisted sprinting has demonstrated efficacy for improving acceleration and sprint speed. However, until recently the recommended sled pulling loads ranged from 7-20 % of your body weight. The main concern was that too great a load would cause a break-down in the sprint mechanics leading to bad habits and therefore a decrease in overall performance. A recent 2017 study revealed that the optimal load is now considered 69-96 % of body weight dependent upon friction surface the sled is being pulled across.
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