Early Mouse Study Raises Questions About Icing Pain

A study from McGill University and Queen’s University examined whether cold treatment changes recovery after inflammation-related injuries in mice. The animals received icing during three days, and researchers monitored pain sensitivity over time. In both injury models, pain lasted roughly twice as long after cold treatment—about 30 days or more instead of approximately 15.

The researchers point to neutrophils, immune cells that arrive early at an injury, as a possible reason. Adding these cells to the paws of iced mice stopped the pain from continuing longer, suggesting that reducing the early immune response may interfere with the body’s normal resolution process. The findings appear in Anesthesiology and are still limited to animal research.

The results do not show that ice is always harmful. Cold treatment may still help when swelling or immediate pain control is the main concern. Instead, the study adds to earlier concerns about heavily suppressing inflammation too soon, including with some anti-inflammatory medicines and steroids. For people dealing with workout soreness or an injury, the research raises a more specific question about when reducing inflammation helps—and when it may slow recovery.