Ice bath

In sports therapy, an ice bath, or sometimes cold-water immersion, Cold plunge or cold therapy, is a training regimen usually following a period of intense exercise in which a substantial part of a human body is immersed in a bath of ice or ice-water for a limited duration.

The method is controversial, with a risk of hypothermia, with the possibility of shock leading to sudden death. Many athletes have used cold water immersion after an intense exercise workout in the belief that it speeds up bodily recovery; however, the internal physical processes are not well understood and remain elusive. Evidence supporting cold water immersion as part of an athletic training has been mixed, with some studies suggesting a mild benefit such as reducing muscle damage and discomfort and alleviating delayed onset muscle soreness, with other studies suggesting that cold water immersion may slow muscle growth and interfere with an overall training regimen.

A 2025 article published in The Washington Post which cites studies researching whether or not cold plunges are beneficial or not adds to growing scientific skepticism about cold plunges, particularly following strength training. Researchers found that immersing limbs in near-freezing water after weightlifting significantly reduced blood flow to the muscles, limiting their ability to absorb protein and recover. This effect could blunt muscle growth and undermine the benefits of resistance training. While cold plunges are often promoted for recovery and mental toughness, the new evidence suggests they may do more harm than good when used immediately after workouts.