Adaptation to exercise in the cold

Changes associated with repeated cold exposures are not as pronounced, or as predictable, as they are with heat acclimation. Therefore, such changes are usually termed out adaptation rather than acclimation. Young has recently described three patterns of thermoregulatory adjustments to prolonged or repeated cold exposures. The first is called habituation, in which physiological responses become less pronounced with each repeated exposure. The second and third patterns involve either a more pronounced metabolic response or an exaggerated insulative response. In the metabolic adaptation, both shivering and nonshivering thermogenesis may be increased. With insulative adaptation, skin vasoconstriction is enhanced.