Back on Track Long Sleeve Shirt provides soothing heat therapy that’s particularly helpful in relieving shoulder, arm, and elbow pain. How do we accomplish this? With Back on Track’s specially designed fabric - Welltex, a blend of polyester with ceramic powder melted into the threads. The ceramic reflects your own body warmth and creates a soothing far infrared thermal heat, which may help to reduces pain and inflammation, relaxes muscles, and increases blood circulation. Heat therapy is a well-recognized method used for healing injured muscles, joints, and tendons. For injury prevention, you can wear this shirt prior to exercise to loosen and warm up muscles. Some people wear it in the winter for additional warmth.