How often should ice be reapplied to an injury during the first day?

Reapplying ice to an injury every 15-20 minutes during the first day is widely recommended because this approach helps manage pain and reduce swelling effectively. Ice application works by constricting blood vessels, which decreases blood flow to the area and helps minimize inflammation. The 15-20 minute interval allows for sufficient cooling to take place without risking frostbite or skin damage.

Using ice too infrequently, such as once every hour or only when swelling occurs, may not provide the consistent relief needed immediately after an injury, potentially leading to increased swelling and discomfort. Additionally, waiting for swelling to occur before applying ice may miss the critical early window when inflammation begins, making proactive management with more frequent applications the better option.