Natures Fitness medicine balls are ideal for simple cardiovascular and strength training workouts, and are a great way to add variety to your workout. Great for any fitness level, whether you are rehabbing from injury or you are an athlete that wants to increase explosive power by doing throwing and punching exercises. These medicine balls are round and can bounce, and that makes for a versatile workout whether you are performing these exercises alone or with a partner. Either way you are guaranteed to work up a sweat.