错误：健身球，瑞士球等
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改正为：
A medicine ball (also known as an exercise ball, med ball, or fitness ball) is a heavy ball, roughly the size of a volleyball or a basketball. Often used for rehabilitation and strength training, it serves an important role in the field of sports medicine. It should not be confused with the larger and lighter Swiss ball.
Medicine balls are usually sold as 5–15 lb. balls and are used effectively in plyometric weight training to increase explosive power in athletes such as boxers, football players, baseball pitchers, basketball players, track and field members and martial artists.
Medicine balls are used by boxing professionals to improve the strength of abdominal muscles. This is done by dropping the ball onto the abdomen of the boxer, simulating a punch coming from an opponent. Other athletes use medicine balls to increase their core strength. One common activity is to have athletes hold the ball against their chest and thrust it at another athlete, who catches it against their chest. This strengthens arm, chest, and leg muscles.
They are also extensively used by secondary schools as a fitness aid. Example exercises include: lifting the ball or performing different exercises (such as sit-ups and leg raises) with the ball in order to increase the strain on a particular muscle.
A medicine ball is also commonly used by athletes who have sustained an injury and seek rehabilitation.
Medicine balls are also used to play powerball, a sport mainly played in Flanders.
[ 本帖最后由 bing2008 于 2008-4-5 12:58 AM 编辑 ]
