It’s important to make the distinction between recovery and adaptation when considering the effects of cold water immersion postexercise. Part of the stimulus for muscle adaptation to any type of exercise involves damage to the local tissues, to a certain degree, which triggers an inflammatory response and frequently delayed-onset muscle soreness, which results in a temporary reduction in strength and range of motion.[1][2] Recovery is the process of restoring normal function after the training stimulus, such as repairing tissue damage and replenishment of fuel stores. In contrast, exercise adaptation is a longer-developing process that involves physiological changes that better equip the body to handle similar types of training stress in the future. Examples of exercise adaptation include the development of larger, stronger muscles from weight training or the development of increased endurance from endurance training such as running, cycling, or swimming.[3]
We consider the effects of postexercise cold water immersion on adaptation from weight training and endurance exercise separately below.
Weight training: Postexercise cold water immersion has a suppressive effect on gains in strength and muscle mass from weight training,[4][5][6][7] so it should be avoided for at least several hours after weight training. Although research to better understand the mechanisms involved is still ongoing, cold water immersion seems to have a suppressive effect on the short-term anabolic (muscle-building) signaling processes that are important for triggering longer-term muscle adaptations.[4]
Endurance exercise: In contrast to the clear suppressive effect on muscle adaptations after weight training, most studies have found that cold water immersion has negligible effects on adaptation from endurance exercise.[7][8][9][10]