How one holds the hands and fingers in the recovery and in the underwater pull has a big influence on how fast you will swim and how well you will sustain that speed. Many swimmers have either been taught or believe that they should use the swimming technique of cupping the hands underwater, holding the fingers and thumb as tightly together as possible. In fact, many do the same on the recovery. By doing so, you will actually reduce the effective surface area of your hand compared to holding the fingers and thumb slightly separated, which is more of a relaxed state.
Because the area between the slightly separated fingers is small, the flow through them becomes turbulent as the hand pushes backward during the propulsive phase of the underwater pull. With a turbulent flow through the small separation, the water slows to the point where the hand acts almost as if it were solid across the separation, effectively increasing its surface area. Spread the fingers too widely and the flow becomes laminar and the hand acts as if it has big holes in it, reducing the effective surface area.
Want proof? Just try sculling in a vertical position in the water using your hands only to elevate your body. Scull hard in order to lift yourself as high in the water as possible. First, try sculling with your fingers and thumb squeezed together tightly. Next, spread the fingers slightly and finally, spread them as far apart as possible. You will feel that the maximum force you can generate is with the fingers slightly spread apart. The difference among the forces you can create with the three hand positions is not trivial.
Besides spreading your fingers apart underwater, there is more you can do to help yourself. It appears that the sensory nerve supplying the baby and ring finger (Ulnar nerve) plays a bigger role in feeling the water pressure than the Median or Radial nerves. As you begin your underwater pull, by bending the ring and pinkie fingers just slightly, as if you were pushing them into a stick of butter, you will have more success in sensing and keeping the pressure against your hands during the pull through. In freestyle the path of the hand should be nearly straight backward, not the side-to-side motion, or the so-called S-shaped pull. Nort Thornton, the great swim coach from Cal Berkeley, reminded me recently that it is this outer part of the hand that is most critical in the feel of the water.
What you do with your hands on the recovery is also very important. Even though the time the hand spends out of the water on each stroke cycle is only about a half second or less, the hand and arm should be as relaxed as possible. Believe it or not, how relaxed your hand, shoulder and arm are during those few tenths of a second have a great influence on their rate of recovery. Ever notice how relaxed Michael Phelps looks on freestyle and buttlerfly recovery? That is why. My former Masters coach, Olympian Troy Dalbey, would tell me to recover my arms with soft hands. By that he meant to let the wrist bend and the fingers relax as the arm swings over for the next stroke.
Finally, extend your hand out fully before it enters the water again. No more slipping the hand in the water in above your head and sliding it forward; too much drag. Don’t place your hand in the water delicately and slowly, what I call the modern toilet seat syndrome. Be aggressive. Whether your hand goes in thumb or fingers first won’t matter too much. Just get the hand in the water quickly. Then rotate it into the right position. Once in the water, spread the fingers and thumb slightly, press down more with the little and ring finger, and get ready for a fast, high elbow pull, straight back, in order to generate some serious force to get you going.