I find it curious that although an increasing number of middle-aged people are going into the water these days for the joy of it few of them ever try to swim well. Despite their obvious love of water, they struggle through it like runaway Percherons. A weekend golfer with no more regard for technique than many swimmers I have seen would be lucky if he broke 130.
I think many people resign themselves to a lifetime of hard labor in the water in the belief that they simply do not have the natural aptitude to swim well or are not in good enough condition. In the past 15 years, above and below water, I have studied the strokes of more than 1,000 swimmers of all ages and varying degrees of competence. On the basis of these observations I am sure that efficient swimming seldom comes naturally but, rather, is a learned skill that can be fairly mastered by anyone willing to devote a little time to it.
A few years back, to satisfy my curiosity about the relevance of natural ability and learning, I went underwater to study the swimming techniques of a dozen puppies, a 2-year-old alligator and a brood of half-grown ducks, none of which had swum a stroke prior to my observations. Although the puppies managed well enough on their first venture in the water, it was obvious that their technique improved in subsequent workouts. Most notably, they began to rely increasingly on their forepaws for propulsion and to minimize the action of their hind legs, using them principally as steering devices. On their first try the ducks tended to list to one side or the other and to swim irregular courses. Although it took the ducks only a few days to become accomplished, there was no doubt that they were learning by the simple process of trial and error. The alligator—the creature one might suspect as being the most naturally endowed—failed completely. On its first attempt, after a few futile movements of its tail and legs, the alligator sank to the bottom of the pool and drowned.
For most land animals, learning to swim is a relatively simple process. Because of the way their limbs are jointed, most of them have no choice but to make their way through the water by "dog paddling" as efficiently as possible. By contrast, because of the greater flexibility of our joints, we humans are able to swim effectively in a number of ways: on our backs, on our sides, or prone. Unfortunately, even when swimming our most efficient stroke, the front crawl, because of the freedom of action we enjoy we are apt to commit a variety of errors. We are liable, for example, to swing our arms too stiffly during one part of the stroke cycle, and we are equally apt to flex our wrists, elbows, shoulders or knees at the wrong moment and in wasteful ways. To put it simply, since there are many things we can do wrong, we have to work harder than other land creatures to get in the right groove.
For those who would like to improve their crawl stroke, the best service I can do by the remote means of the printed page is to point out the most common mistakes and offer ways of correcting them. Although it is possible for you to diagnose your own faults to some extent, to make the most of my advice you should have someone observe your actions. It helps if two swimmers work together, analyzing each other's stroke.
Generally speaking, there are two kinds of errors that affect a swimmer's efficiency: 1) those that increase resistance in the water unnecessarily, and 2) those that use energy without contributing sufficient propulsive force. Even when the body is in its most streamlined posture, a racing dive, it encounters resistance of several sorts. Then skin friction itself disturbs the laminar flow of the water. Although such friction has a great deal of effect on fast-moving objects, it is a minor consideration even for the fastest sprint swimmers. In moving through the water, the body is also subject to frontal resistance as well as to drag, or eddy resistance, both of which are deterrents.
Crawl swimming is essentially an integration of four distinct actions: the cyclical stroking of the arms, the flutter kick, the rotating of the head to one side for air and a necessary rolling of the whole body on its long axis to facilitate the recovery of the arms out of water. The swimmer who makes these actions with little side-to-side movement of the body and with little deviation of the body from the horizontal plane is minimizing both frontal resistance and drag.
Most of the excessive resistance that inept swimmers create is the result of faulty stroking or breathing technique. One of the most common faults I find among casual swimmers is the extravagant way they recover their arms out of water. Instead of lifting the elbow up and letting the hand and forearm come forward fairly close to the body as each arm completes the propulsive phase of the stroke underwater, many strugglers barely bend their elbows at all, swinging their arms forward in a flat, wide arc (see drawing above left). Although the arm itself encounters little resistance as it swings through the air in this manner, the effect is still detrimental. As Isaac Newton first propounded, for every action there is an equal and opposite reaction. The wide swing of the arm to one side tends to throw the legs or hips (or both) out of line on the opposite side. The wiggling hips and the legs create resistance, but the wide-swinging arm is the real culprit.
Many swimmers who recover their arms in a flat arc compound the error. At the end of the recovery, instead of entering their hand in the water directly forward, in line with the shoulder, or slightly inward toward the center line of the body, the wide swingers tend to bend the elbow and sweep the hand across the center line of the body. When the arm crosses over this way, the swimmer must straighten his elbow to properly start the press of the hand downward and backward through the propulsive phase of the stroke. In so doing, rather than pushing downward and back in a direct line in the first part of the propulsive action, he is actually executing somewhat of a lateral motion, thus diminishing the force of the stroke as well as moving the body slightly out of line in the opposite direction.
Untutored swimmers who have fairly good recoveries often commit a different sort of error: at the end of the recovery they overreach, extending the shoulder excessively. You can appreciate the effect of this error by standing erect and holding one arm overhead, then bringing it down in front of you. If you do this without extending the shoulder, you will find that the action has almost no effect on the rest of the body. Then, if you assume the same position but extend the shoulder upward to get a few more inches of reach before lowering the arm, you will feel your whole torso being pulled out of line.