Cold packs are great to reduce pain caused due to stress or injury. An instant cold pack is rather useful during emergencies and sports injuries. Cold compress comes in several forms and usually it is a frozen gel that helps reduces inflammation and brings relief. It should be applied soon after the injury is sustained.
Hot packs are ideal for sore muscles and to relieve pain caused by old injuries. An instant heat pack does not require batteries or electivity and is reusable. A heat pack is also used in physical therapy to loosen the muscles and relieve the discomfort caused due to injury or strain.