Physical therapists, trainers, and athletes use foam rollers to relieve muscular pain and tightness (often called "adhesions", "knots", or "trigger points"). But conventional foam rollers have smooth surfaces that further compress soft tissue. The RumbleRoller was created to perform this therapy more effectively. The surface of the RumbleRoller contains specially designed bumps that are firm, but flexible, much like the thumbs of a massage therapist. As you roll over the top of the RumbleRoller, the bumps continuously knead the contours of your body, gently stretching soft tissue (muscle and fascia) in multiple directions. This action erodes trigger points, helps restore flexibility, and brings quick relief to common types of muscular pain. Available in 2 convenient sizes and densities.