A core training ball is a piece of exercise equipment that allows an athlete to perform a variety of exercises while sitting on it or while certain parts of the body are on the ball. Most of the exercises that make use of a core training ball target the body's core — muscles such as those in the abdominal area, those in the lower back and the obliques. Performing exercises with a core training ball can increase an athlete's overall core strength, which can be very beneficial to the athlete because most athletic movements originate or depend on the core to some extent.
Before using a core training ball, it is important to make sure that an athlete has the correct size ball and that he or she inflates it correctly. The size of the ball should be relative to the athlete's height. Core training balls range in size from 18 to 34 inches (45 to 85 cm). Generally, an athlete should use a exercise ball that allows him or her to sit on the ball with the feet on the floor while maintaining a 90 degree angle in the knees. If this is not possible, it is better to have a ball that is slightly larger, so that the hips are higher than the knees, than it is to have a ball that is too small.
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After an athlete has the correct size core training ball, there are a number of core strength exercises that he or she can perform. The most common balance ball exercise is simply to balance with the buttocks on the ball and the feet planted firmly on the ground, then to lean back and perform crunches. Athletes can also rest their back on the top of the ball and then, with the use of small hand weights, perform different types of bench presses. The benefit of using the core training ball for these kinds of exercises is that the ball requires the athlete to work to maintain balance. This balance translates into a workout for the core muscles and thus increases the overall intensity of the workout and the benefits that the athlete receives.
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In addition to core strength exercises that require the athlete to balance on the ball, a balance ball also can be useful for exercises in which the athlete lies on the floor. The athlete can rest his or her feet on the ball while performing various types of crunches. Also, the athlete can lie on the floor while gripping the ball between his or her legs in order to perform leg lifts, or in order to pass the ball between the arms and legs while performing an alternative to standard crunches.
In addition to these exercises, a core training ball can even provide an effective core strength exercise when an athlete is not working out. Using a core training ball instead of an office chair requires than an athlete use the core muscles to remain balanced while performing tasks that normally would provide very little physical benefit. It also forces the athlete to maintain proper posture, which can help to alleviate back pain.