A foam roller is a lightweight, cylindrical tube of compressed foam. They are used for many reasons including increased flexibility, reduced soreness, and eliminated muscle knots. Foam rolling is as a method of self-myofascial release. Studies show that the best results occur when one uses the foam roller for 30 to 90 seconds on each muscle and combines with static stretching. Rollers come in different firmness and size. The firmness (often identified by the color) can range from soft to firm, soft being best for beginners.