How to play swimming???

A number of swimming styles have been developed based on the implementation of some or all of the following principles:
The torso and the legs should be kept as parallel as possible to the surface of the water. Dropped legs or a slanted torso dramatically increase drag. The hand should be extended forward of the head as much as possible. This increases the average length at the water-line, substantially increasing speed.

Resistance swimming is one form of swimming exercise. It is done either for training purposes, to hold the swimmer in place for stroke analysis, or to enable swimming in a confined space for athletic or therapeutic reasons. Resistance swimming can be done either against a stream of moving water (often termed a swimming machine) or by holding the swimmer stationary with elastic attachments.

Swimming is primarily an aerobic exercise due to the long exercise time, requiring a constant oxygen supply to the muscles, except for short sprints where the muscles work anaerobically. As with most aerobic exercise it is believed to reduce the harmful effects of stress. While aerobic exercises usually burn fat and help with losing weight, this effect is limited in swimming[citation needed], even though being in cold water burns more food energy to maintain body temperature.

The reason that swimming does not significantly reduce weight is still poorly understood, but seems to be related to the better heat conduction of water. A number of reasons are suspected.

* Water cools the body much faster than air and most researchers believe that subsequently the body aims to maintain a layer of fat under the skin for insulation.
* It is believed that appetite decreases as the body temperature increases, as for example during exercise. However, during swimming the body is cooled down almost instantly as the surrounding water is usually cooler than the body temperature, and some researchers believe that this may actually increase the appetite. This assumption is not yet proven by research.
* Fast swimming requires a high level of effort, meaning glycogen rather than fat is burned. Prolonged exercise at lower intensity is better for fat-burning.
* Some researchers also believe that the metabolism of the body increases at higher body temperature, burning more food energy. Again, during swimming the body is cooled down by the surrounding water, reducing the metabolism, and subsequently the amount of food energy burnt. This assumption is also not yet proven by research.
* There is also a theory that people with a genetically higher body fat content tend to be more successful as swimmers since the increased buoyancy of the fat aids in floatation or the rounder shapes offer less resistance to the water.

It is surprising that, while swimming provides many health benefits, it offers almost zero benefit for bone density[1]. Some additional form of exercise is required if maintaining bone density is of importance.

Swimming exercises almost all muscles in the body. Usually, the arms and upper body are exercised more than the legs. In competitive swimming, excessive leg muscles can be seen as a disadvantage as they consume more oxygen, which would be needed for the muscles in the arms, although this depends on the swimming style. While breaststroke generates significant movement with the legs, front crawl propels the body mainly with the arms.

not enough space,go to the web for more information,too bad for the space limited!=[[[
hope that i can help you!

回答 (2)