Many people believe jumping is all in the legs.  But take a look at all the great leapers such as Michael Jordan, Darius Miles, and  Kenyon Martin.  They all have one thing in common: low percentage of body fat, abs of steel, and strong backs.  Even with strong calves, jumping high is not possible if not supported by strong abs and back muscles, otherwise known as your core muscles.

Medicine Ball training is one of the most effective ways to  strengthen your abs and lower back.  Here are three of the most killer exercises you can do with a Medicine Ball which strengthen  your abs and back:

1. Crunches  - Medicine Ball near or on your forehead, knees bent, back on the floor.  Come up halfway to your knees and go back down without touching your back on the ground.

2. Russian Trunk Twist - Back on the ground, arms spread out,  Medicine ball between knees.  Rotate knees from left to center to right.

3. Forward throw - Hold the Medicine ball behind your head and throw over your head forwards.
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