Swimming
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Swimming

Swimming

I INTRODUCTION

Swimming, act of moving through the water by using the arms, legs, and body in motions called strokes. The most common strokes are the crawl, backstroke, breaststroke, butterfly, and sidestroke. Swimming is an integral part of almost all water-based activities. It is also a competitive sport itself.

Some scientists believe that human beings are born with an instinctive ability to use their arms and legs to stay afloat. That instinct, however, disappears within a few months after birth. Later in life many children and adults learn to swim in order to be safe around the water, to have fun, and to participate in competition.

II SWIMMING FUNDAMENTALS

People can swim in any body of water large enough to permit free movement. These areas include ponds, lakes, rivers, the ocean, and pools. Most people enjoy swimming in water that is between 18° and 29°C (64° and 84°F).

A Learning to Swim

In many parts of the world, people learn to swim by imitating others, most often their parents, brothers, sisters, and friends. Most youngsters in North America also take lessons at swim clubs, community centers, schools, or recreational facilities. In addition, the American Swimming Coaches Association (ASCA) and the American Red Cross sponsor programs that teach children about water safety.

Instructors teach students skills that will make them safe, efficient, and confident swimmers. Beginners first put their heads in the water and blow bubbles by exhaling. Gradually, students progress to floating, treading water, and ultimately, learning the techniques of the major strokes.

Students use various pieces of equipment during these lessons. Water-wings are inflatables worn around the upper arms; they allow children to float easily. Kickboards are buoyant boards that students can rest their arms on; this keeps their upper bodies afloat and allows them to concentrate on kicking correctly. Pull-buoys are foam floats that swimmers hold between their thighs to keep the lower body high and flat on the surface of water; using them, students can learn the arm and upper body movements of various strokes. Paddles are small, firm boards fitted over the hands; they force students to pull their arms through the water correctly. Fins worn on the feet allow swimmers to go faster and to develop proper body position and power.

B Hazards and Safety Measures

Individuals should not swim in conditions that their ability and experience will not allow them to handle. For inexperienced recreational swimmers, many safety hazards exist—even in a pool. These hazards include misjudging a dive and hitting one’s head on the bottom, holding one’s breath too long, becoming exhausted, and experiencing sudden cramps while too far from shore or other swimmers.

In rivers and oceans, all swimmers should respect the power of nature. Powerful waves, tides, and currents can easily overpower even the most experienced swimmers, sweeping them out beyond safety or throwing them into coral or rocks. Caves pose additional dangers because swimmers can be trapped inside them. Swimmers must follow the instructions of lifeguards and obey posted information about water conditions, tides, and other dangers such as jellyfish or pollution. A good precaution for children is the buddy system, in which each child is paired with another while in the water. This system ensures that no person is swimming alone and that if an emergency does happen, the lifeguard can be notified immediately.

III THE MAJOR STROKES

Four of the five main swimming strokes—the crawl, backstroke, breaststroke, and butterfly—are used both in competition and recreation. The fifth major stroke, the sidestroke, is slower than the competitive strokes and is used primarily as a recreational and life-saving technique.

A Crawl

The crawl is the fastest and most efficient swimming technique. It is also called the freestyle, because swimmers use it in freestyle events, which allow the use of any stroke.

To swim the crawl, a swimmer travels through the water with the chest and head pointing downward toward the bottom. The legs move in a flutterkick, moving up and down quickly and continually. Each arm stroke begins as the right arm is brought in front and slightly to the right of the swimmer’s head and into the water. When the right hand enters the water, the right elbow should be above the surface of the water and the body should be tilted slightly to the left side. At the same time, the left arm accelerates underneath the water in a pulling motion down the length of the body.

After the right arm enters the water, the body naturally rolls to the right so that the body is horizontal to the water surface. The left arm continues through the stroke at the swimmer’s side. The swimmer continues to extend the right arm forward, and the body begins to roll onto its right side.

As the right arm begins to pull the swimmer forward, it increases the body’s tilt to the right side, and the left arm exits the water near the swimmer’s hip.

The swimmer then brings the left arm forward to enter the water while the right arm travels down the swimmer’s side. As the left arm enters the water and the right arm exits, the swimmer’s body begins to turn to the left side again, and the swimmer begins the stroke sequence once more.

In the crawl, turning the head to breathe is a simple, easy motion that should be

coordinated with the body roll. As the body tilts completely to the right or left side, the swimmer should roll the head to the same side and take a breath. After inhaling, the swimmer puts his or her face back in the water, looking toward the bottom of the pool. The swimmer exhales slowly through the nose or mouth as the body rolls toward the other side.

B Backstroke

The backstroke is the only stroke that is swum on the back, with the swimmer looking up. Backstroke swimmers therefore cannot see where they are going. Because the face is out of the water, swimmers need no special breathing technique. Backstrokers use the same flutterkick that crawl swimmers do.

At the beginning of each arm stroke, the swimmer extends the right arm so it enters the water slightly to the right of the head. The palm should be facing away from the swimmer and the pinky finger should enter the water first. At the same time, the swimmer moves the left arm through the water below the left side of the body. Once in the water, the right arm begins pulling the swimmer forward by bending at the elbow. At the same time the swimmer holds the left arm straight as it reaches the hip and lifts it out of the water. As the right arm continues to pull, the swimmer rotates slightly onto the right side and swings the left arm up above the head.

As the swimmer finishes the right arm’s stroke along the body, he or she begins to rotate toward the left side as the left arm reaches to enter the water above the head.

As the left hand enters the water, the body completes its roll to the left side and the right arm lifts out of the water. Continuing these motions, the swimmer moves forward.

C Breaststroke

The breaststroke is one of the easiest and most relaxing strokes for novices. Competitive swimmers, however, find it difficult because it uses more energy than the crawl and backstroke when swum at a fast pace. The breaststroke has undergone major changes since it was introduced in the 17th century. Most swimmers now use a technique called the wave breaststroke, which Hungarian coach Jozsef Nagy developed in the late 1980s.

To swim the wave breaststroke, the swimmer enters the water with the body streamlined, facing the pool bottom with arms and legs fully extended. To begin the stroke, the swimmer sweeps the arms out with the hands facing outward and bent slightly upward at the wrist. When the swimmer’s body and arms form a T-shape, the swimmer bends each arm at the elbow. The elbows remain near the surface of the water, while the forearms and hands, pointing toward the bottom of the pool, sweep inward and underneath the chin. The swimmer shrugs the shoulders, looks down, and arches the back as the arm sweep pulls the body forward. The swimmer then raises the feet to the surface of the water, bends the knees, and spreads the legs. The thighs should remain in line with the body.

As the head and upper torso clear the surface of the water, the swimmer inhales and lunges forward with the arms. During this movement the swimmer turns the feet outward and kicks backward. The swimmer then returns to the basic streamlined position and repeats the stroke.

D Butterfly

The butterfly stroke is powerful, graceful, and fast. More than any other stroke, the butterfly relies on good technique. Developed between 1930 and 1952, the butterfly is swum with an undulating motion. The arms are brought forward over the water’s surface, then brought back together in front of the body simultaneously. Each arm stroke is complemented by two dolphin kicks, meaning the feet are kept together and brought down then up again, much like the motion of a dolphin’s tail.

The swimmer begins the butterfly with the body in the basic streamlined position and the head facing downward. The arms enter the water with the hands facing outward, as the swimmer lunges forward, submerging the head and chest slightly. At this point the swimmer makes a light downward kick with both feet. The body glides forward, and the hands catch water and begin to pull.

The pulling stroke begins with the hands facing outward and the elbows near the water surface. The swimmer pulls the hands down so that they come together under the body. The legs start the second downward kick.

When the swimmer then pulls the arms down to the hips, the motion forces the head and shoulders above the surface of the water. This positioning enables the swimmer to inhale.

The swimmer finishes the arm pull with a sweeping motion that brings each arm along the sides with the palms facing in. When the second downward kick is completed, the swimmer swings the arms slightly out of the water and glides forward. Another stroke cycle begins as the swimmer plunges the arms back into the water above the head.

E Sidestroke

The sidestroke evolved out of the breaststroke technique in the 19th century, primarily because swimmers wanted to swim faster. Swimmers originally thought that because the body remained on one side throughout the sidestroke cycle, there would be less resistance. However, because the sidestroke generates less force than the other strokes, it turned out to be slower. The sidestroke has remained a popular recreational stroke for novices. It is also used as a life-saving technique because the lifesaver’s head remains above the water at all times and one arm stays free to help the distressed swimmer.

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