Pain is often the result of muscles around an injured area tightening to protect the area, cryotherapy helps remove muscle memory allowing those aiding muscles to relax and stand-down. 

Cryotherapy constricts blood vessels and reduces blood flow to the affected area to limit swelling. Once the session is over, oxygenated blood, which is rich in nutrients, is then directed back to all parts of the body including to the injured area promoting faster healing and clear blood flow for a reduction of pressure around the area of injury or pain limiting inflammatory cytokines. The fewer cytokines the less inflammation and less swelling and pain.