The Back on Track Sweatshirt is ideal for problems in the shoulders, shoulder blades and elbows, as well as for pain in the neck and spine. As the Back on Track fabric is dependent on skin contact in order to be most effective, the top's size is less important if one is affected by pain in the shoulder region as the material always has body contact in these areas. However, it is easy for an air pocket to appear between the top and the lumbar back region when standing up. So for those affected by backache then the Back Brace and Mattress Overlay are highly recommended as well. The polypropylene top is smooth and soft to wear. This fabric is extra durable and wicks away sweat effectively and doesn't get burled as the polypropylene fabric has longer fibres than simple polyester. This garment may even be used as underwear or an extra layer during physical activity as the polypropylene textile breathes and wicks sweat away. Ideal for use in combination with the Long Johns polypropylene underwear. Comes in a range of sizes (Extra Small, Small, Medium, Large, Extra Large, XX Large and XXX Large).