>> Gretchen Reynolds, The New York Times Published: 22 Apr 2021 12:26 PM BdST Updated: 22 Apr 2021 12:26 PM BdST Little has been known about how icing really affects sore, damaged muscles at a microscopic level but a new study in the Journal of Applied Physiology done in mice suggests that icing muscles after strenuous exercise is not just ineffective, it could be counterproductive. The New York Times After a particularly vigorous workout or sports injury, many of us rely on ice packs to reduce soreness and swelling in our twanging muscles. But a cautionary new animal study finds that icing alters the molecular environment inside injured muscles in detrimental ways, slowing healing. The study involved mice, not people, but adds to mounting evidence that icing muscles after strenuous exercise is not just ineffective; it could be counterproductive.