While the arm movements can be greatly varied, there can be, in the nature of things, no such variation in the action of the legs. It is said, and truthfully, that the motion of the legs of a human swimmer are much like the motion of a frog's hind legs when swimming. That is, the boy draws his legs up simultaneously and kicks them out in the same way, but in so doing he is not imitating a frog, for if he works the limbs together there is no other possible way in which he can do it under water. The frog's breast stroke is another story. A man swims very much as does a frog, though he cannot do so well under water as the amphibian. The legs are kicked in the same way and there is the same motion of the arms of one as of the forelegs of the other.
Some swimming teachers believe that the main reliance is the legs, but this has not been my experience, and I have seen many swimmers in many waters. The legs steady the body, but it is the arms that make for speed as well as for steering, though on the back it is the legs that do the business.
HOW TO DO IT
Bring your hands together under your chin, with the palms down, fingers straight, close together, and pointing in the direction you are about to move. Next shove the two hands straight out in front of you, keeping your thumbs touching. As your hands are pushed forward, kick backward with your legs, as previously described. When the knees are straight, the legs will be spread wide apart. Bring them together, and, if you time this properly, your position will now be that of an arrow, the point being your extended hands.
While the arms and legs alike do their share in the propulsion of the body, the legs perform by far the most important work, and the importance of a good "kick" cannot be too strongly urged. Though the action of the soles of the feet upon the water helps the "drive," the momentum is also given by the "wedge" of water embraced and driven backwards by the action of the backs of the thighs and calves, as they almost come together at the completion of the leg stroke. Hence, the wider the stretch the more powerful the "drive," and the beginner should try to rival as closely as possible that acrobatic performance known as "the splits" when trying to master the kick. The action of arms and legs is alternate; that is to say, when the legs are making their sweep, the arms are thrown forward to their fullest extent, thus helping to sustain the upper part of the trunk, and serving as a prow or cutwater; then, during the first part of the arm stroke, the legs, almost touching after finishing their work, remain stiff and extended, so as to offer as little resistance as possible. These positions are but momentary, but their rigid observance is necessary to ensure pace with the least expenditure of force.
THE ARMS
The breast stroke will require some practice, and this can be helped by out-of-the-water exercise. Close your fingers tightly, but not so as to be very conscious of the effort. In this position, bring them up till the chin rests on the two thumbs, which are side by side and parallel. Next separate the hands, fingers still close together, shoot them edgewise as far in front as you can reach, then with the flat palms and closed fingers to the resisting water, draw them smartly back, like oars.
For the second stroke, draw the arms edgewise to the first position and repeat as often as may be necessary. This exercise will strengthen the arm and shoulder muscles and greatly facilitate the movements when you come to use them in swimming.
Be careful always to bear in mind the following rules: Keep the head thrown back so as to clear the mouth and chin. Try to swim as low as possible. The lower and the nearer level the plane in which the body lies in the water, the less the waste of power and the greater the speed, so that all rising and falling must be avoided, and nothing seen below the chin. Always keep the trunk steady and the spine hollowed, avoiding all squirming, wriggling and bending, while the motions must be made steadily, avoiding all hurry. Exhale your breath when the hands are extended in front supporting the head, and inhale as they are brought back—an action which expands the chest and gives you almost instinctively the signal for taking breath, which should be inhaled through the nose as much as possible.