An exercise ball is one of the most affordable and versatile pieces of workout equipment you can add to a home gym. Exercise balls are great for people of all fitness levels, can be used for everything from weight lifting to yoga, and come in a wide variety of sizes.
Exercise balls can be a a great way for runners to work on core stabilization techniques, and can even function as an office chair, helping you strengthen your back, engage your core, and make sitting at a desk all day a bit more tolerable.