Entry of the hand into the water is made with the thumb and index finger first at a point slightly inside the shoulder and about half an arm's length in front ahead of the shoulder. The hand now enters the water at a 40-degree angle, cutting a smooth pathway.
To reduce drag, the arm entry must be smooth. The fingertips, hand, forearm, elbow and shoulder follow one another in a streamline. Don't be one of those swimmers who engage the water with a straight-arm landing on top of the water. The wave drag resulting from this technique is significant, and the hand and arm are not in a good position for making the downsweep.
More: Sculling DrillsTwo: The Downsweep and Catch
As you stretch forward along a slowly descending arc (over a barrel) the hand traps water as the wrist is slightly flexed outward and downward, with the fingertips pointed toward the bottom of the pool. There should be minimal downward forces here. This is a position move and low on the velocity and intensity. The fingers should be spread slightly apart to increase the surface area of the hand. The forearm and hand continue downward; deflecting water away from the hand (the leading edge is the thumb, pitched slightly away from the body to divert water to the outside. The elbow is flexed and higher than the hand.
The bottommost point of the downsweep (over the barrel) is called the catch.
The next movement after the hand enters the water is the downsweep. This term may be misleading, as the swimmer really shouldn't apply downward force here. Rather, the movement should be a gentle sweep of the forearm and hand as the elbow remains high (above the hand) and slightly flexed. Its primary purpose is to position the hand and arm for the insweep and upsweep phases of the stroke.
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What is the correct way to do the downsweep and catch? First, the direction of the hand and arm is forward and downward, with the wrist flexed as the sweep is initiated. At this point, the elbow flexes as the forearm and hand move slightly downward, outward and backward. Keep in mind that this is where the least force is applied. The whole purpose is to set the hand to make the catch (think over a barrel). The catch occurs at the end of the entry, and the elbow flexes higher up due to the pressure (lift) on the hand. The hand is now ready to begin the insweep, as the pitch and angle of attack now change (sweep and round off) toward the midline of the body.
Three: The Insweep
The hand is pitched at 40 degrees and rounds off, sweeping inward and upward to at least the midline of the body. Sculling drills are great for learning how to deflect water with the hand and underside of the forearm and are highly recommended.
When the downsweep and catch have ended, the insweep begins. At this point, there is a natural tendency for the hand to begin moving inward, upward, and backward toward the midline of the body. The insweep is the first larger propulsive part of the stroke. The swimmer will feel lift and considerable hand pressure from the water during this move.
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