Medicine balls are fitness balls of various weights, ordinarily ranging from 2 to 20 pounds (around .9 to 9.1 kilograms), that are used in strength training workouts and sometimes in physical therapy. A medicine ball is generally about the size of the chest, although they are available in a variety of sizes. Some medicine balls are produced with one or two handles that allow for a closed hand grip instead of the open hand grip required for exercise with an ordinary medicine ball. These handled balls allow for a swinging motion that provides the athlete with the option of performing exercises similar to those done with a kettlebell. A medicine ball with two handles is known as a double grip medicine ball and allows the user to perform two-handed strength training exercises.
Unlike traditional strength training weights, such as dumbbells and barbells, medicine balls allow for a range of exercises, including throwing and rolling. Medicine balls can be thrown back and forth between two individuals to work a broad range of muscles, both through the pushing motion of the throw and the stabilizing motion of the catch. Throwing a medicine ball works the core muscles, the chest, legs, and arms. The round shape of the ball makes it useful for adding resistance in floor exercises, including sit-ups and variations on the push-up.
A double grip medicine ball increases the number of exercises that can be performed. The double grip allows for the ball to be held in front of the chest to increase the resistance during sit-ups and to be held for lunge and squat exercises. In addition, a double grip medicine ball works well for overhead shoulder presses and chopping exercises that require the grip of both hands.
Handles add the component of swinging to the range of exercises one can perform with an ordinary medicine ball. These handles, whether one handle or the two handles of a double grip medicine ball, are either permanently attached to the ball or removable for a more versatile ball that can function as both an ordinary and handled ball. The swinging action allowed for with handles adds further to the already broad range of muscles targeted by fitness ball–based exercises. Core muscle stabilization is required for proper swinging of the ball, and as a result medicine balls are commonly used in physical therapy rehabilitation that demands core stabilization.
