Misconception No.3: The forearm is positioned vertically as the pull begins.
If the elbow is flexed at the beginning of the pull, to position the forearm vertically, the hand moves laterally (to the side of the shoulder as shown in Figure 3, left). As force is applied during this motion, torque is generated about the antero-posterior (front to back) axis and the body twists (or the swimmer must kick sideways to compensate). Either option is disadvantageous in freestyle. In addition, the arm is weakly positioned for the push phase.
Figure 3. Ineffective vertical forearm (left) and effective diagonal forearm (right).
It is far more effective to diagonally orient the forearm as the pull begins by moving the hand from in front of the shoulder (at the completion of the arm entry) to a point directly beneath the head (as shown in Figure 3, right). The swimmer benefits from improved leverage on the pull phase and also has the arm in a stronger position to generate more force on the push phase.
Just because certain freestyle technique elements are popular, exhibited by top swimmers, or have even become conventional wisdom doesn't mean they are effective. The three elements listed above are prime examples. Fortunately, swimming science has progressed so that we now have considerable information to accurately evaluate technique elements.
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