This page presented by Amazon Exercise & Fitness
To achieve a balanced body position ON the water, the spine should be firmly held in a neutral alignment without tension in the neck and shoulders. Think of the spine as a metal rod, off which everything hangs. (MYTHBUST 1: the water WILL support you and you can use your energy only to move forward). The quad (in the front of the legs), lower abs and oblique muscles help hold your lower half up, so make sure there is no bend in the knees. (MYTHBUST 2: the kick comes from the hips and is with straight knees. MYTHBUST 3: the kick does not help forward propulsion unless you are sprinting, distance swimmers want to use the legs only to balance the stroke) Flexible ankles also help by reducing resistance; keep feet floppy (but knees straight). Using fins will aid in establishing the correct body position and also help increase ankle flexibility.
By keeping the head in neutral with eyes looking straight down at the bottom of the pool and water level at the ears, the hips and legs are able to stay balanced near the surface of the water. Remember, the head is a 19 pound counterweight, and any lift of it up and out of the water will cause your legs to sink. When breathing, it is important to keep your head in contact with the water; have one ear and one goggle lens in the water as you roll (at the hips) and turn slightly for the breath. . (MYTHBUST 4: you do NOT yank the head up for air. You will have a pocket of air lower than the surface of the water at both ears IF you keep your head in the water...see next section).
The breath is relaxed and soft. Inhale through the mouth and exhale (while the face is in the water) through the nose, mostly, and the mouth. Do not try to completely fill and empty the lungs. The inhale is a small, but deep, "belly breath", as in yoga, that is taken to the bottom of the lungs. The exhale is removing the bad stuff at the top. So, you always have some air in your lungs to keep you buoyant. (MYTHBUST 5: you must exhale while your face is in the water because there is not enough time to do both when you turn for air).
This is the most important body part in swimming. It is about the elbow that an effective and forceful rotation occurs in the pull and it is about the elbow that rotation enables a relaxed recovery of the arm. Imagine you are a marionette with strings from your elbows to the end of the pool ahead of you. You cannot have them too far forward. In fact, it is the "dropped" elbow that is the give-away signal that a swimmer is a novice.
As hinted above, the hands DO NOT lead the recovery, otherwise, the elbows will drop. The hand follows behind the elbow, almost dragging along the surface of the water until the elbow cannot go any further forward. Then the forearm swings into action, drops, and the hand knifes into the water as if you are sending it through a mail slot. Then the hand slides in the water, shooting forward, at a 25º angle (MYTHBUST 6: the hands and arms are not extended at the surface of the water; they are fully extended, but at an angle down). The correct placement of the hand entry is at least shoulder width, or wider. (MYTHBUST 7: the hands do NOT enter in front of the face or anywhere near the midline of the body).
Timing the catch is the most critical part of the stroke and the most misunderstood. (MYTHBUST 8: the stroke is not a rotary movement with arms in opposition). Only one hand/arm moves at a time. This is practiced best with "catch-up" drill, where one arm strokes and recovers while the other waits patiently in front, fully extended at a downward angle, with slight pressure against the water. Then the patient arm strokes and recovers...etc. The actual catch happens after the hand shoots forward and "skates", while waiting for the other hand to begin recovery, and then grips onto the still water out in front, about a foot deep and wider than the shoulders. The catch entails another rotation about the elbow, not a drop of the entire arm. (MYTHBUST 9: the power part of the pull is shallow and a result of the forearm rotating about the elbow, as if you are "pole vaulting" over your anchored hand.) The elbow stays put, very near the surface of the water, as the forearm rotates around it and finishes pulling at the hip. Go no further back because your elbow is now in a perfect position to lead the recovery. This shorter stroke also means your patient arm does not have to wait as long. (MYTHBUST 10: the "S" pull is now obsolete, do not pull in under your body, keep it wide, short, and parallel to your side). Once the hand reaches the hip, the hip should be rolled up and out of the way of the hand...see next
(MYTHBUST 11: the roll is at the hips, NOT with the shoulders)The body rotation that allows you to breathe, recover with high elbows, and provides the power to the pull (by way of the lats, from your core) is a hip roll. Remember to let the (small) kick go sideways with the hip roll. The feeling of keeping the shoulders as stable and flat as possible keeps your head in a great place to catch air. This position drives your leading (patient) arm forward and gives you room to recover with high elbows. If you do not find air when you roll, you are probably driving your shoulders down into the water, and your head must follow.
Once your pull has reached your hip, the elbow is able to lead the recovery. (Remember the marionette strings?) It may feel as if you are taking your hand out of your pocket. If not, you pulled too far back. (MYTHBUST 12: you do not need the flashy finish of a long stroke. This utilizes the triceps only which are very small muscles that deplete quickly and prevents your elbow from being ready to lead.) Hand and fingertips are relaxed and the elbow is always ahead of the wrist. See "elbow" above.
In order to make corrections necessary, you should focus on one point at a time and try to layer the drills. For example, start with the catch-up timing which amounts to alternating one-arm swimming. Then add the elbow-lead recovery to that. Once some new movements can be accomplished without much thought, add something else. Keep in mind that the weirder it feels, the more likely correct the stroke. No one does this "naturally," except fish. Try to be as fluid and relaxed as possible. If you are tense and mechanical, it will not work. Be patient, be relaxed, and be buoyant!