<P> Normally, the face is in the water during front crawl with eyes looking at the lower part of the wall in front of the pool, with the waterline between the brow line and the hairline . Breaths are taken through the mouth by turning the head to the side of a recovering arm at the beginning of the recovery, and breathing in the triangle between the upper arm, lower arm, and the waterline . The swimmer's forward movement will cause a bow wave with a trough in the water surface near the ears . After turning the head, a breath can be taken in this trough without the need to move the mouth above the average water surface . A thin film of water running down the head can be blown away just before the intake . The head is rotated back at the end of the recovery and points down and forward again when the recovered hand enters the water . The swimmer breathes out through mouth and nose until the next breath . Breathing out through the nose may help to prevent water from entering the nose . Swimmers with allergies exacerbated by time in the pool should not expect exhaling through the nose to completely prevent intranasal irritation . </P> <P> Standard swimming calls for one breath every third arm recovery or every 1.5 cycles, alternating the sides for breathing . Some swimmers instead take a breath every cycle, i.e., every second arm recovery, breathing always to the same side . Most competition swimmers will breathe every other stroke, or once a cycle, to a preferred side . However some swimmers can breathe comfortably to both sides . Sprinters will often breathe a predetermined number of times in an entire race . Elite sprinters will breathe once or even no times during a fifty - metre race . For a one hundred metre race sprinters will often breathe every four strokes, once every two cycles, or will start with every four strokes and finish with every two strokes . In water polo and water rescue, the head is often kept out of the water completely for better visibility and easier breathing, at the price of a much steeper body position and higher drag . </P> <P> The body rotates about its long axis with every arm stroke so that the shoulder of the recovering arm is higher than the shoulder of the pushing / pulling arm . This makes the recovery much easier and reduces the need to turn the head to breathe . As one shoulder is out of the water, it reduces drag, and as it falls it aids the arm catching the water; as the other shoulder rises it aids the arm at end of the push to leave the water . </P> <P> Side - to - side movement is kept to a minimum: one of the main functions of the leg kick is to maintain the line of the body . </P>

What is a front crawl stroke in swimming