Short-Stepping The Split Jerk - How To Fix It
If you short-step your heavier jerks, your footwork may not be the problem. The issue is often a lack of time and space to move your feet into the full split position because of an inadequate upward drive on the bar and/or poor timing.
Sometimes this is the result of believing you must only move down with the arms. Instead, focus on trying to continue elevating the bar with the push of the arms—the body will be forced down as needed with this effort as the feet move into the split because the absence of resistance, and more of the bar’s upward momentum will be preserved for more total bar elevation.
With a short or weak drive, bar momentum and elevation is reduced, and it takes longer to separate the front foot to split. This means the foot will be forced back down to the floor before it can cover the distance to achieve the necessary split depth to lock the bar out overhead.
To improve your timing and drive, train the following exercises. In each, focus on a long leg drive, reaching the trunk up through the bar and continuing to push the bar up with the arms.
Push Press + Jerk
Jerk Behind the Neck + Jerk
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Fernando Reis video by Hookgrip