Age Specifics of Homeostasis Response to Cold Stress in Wistar Rats: Endurance Improvement or Disorganization?

Cold exposure, especially in combination with exercise, is a common procedure to fortify the body. However, its effects in old age are poorly understood. Using the homeostasis stability coefficient as an indicator, the body response to a 20-min swim in cold water was for the first time studied comprehensively in old and young Wistar rats. Effects on the hormonal, hematological, and morphofunctional systems of the liver and thymus were assessed. Unfavorable age-related changes in the stability of homeostasis were observed in old rats. The changes complicated the recovery after cold stress and required the involvement of a greater number of homeostatic mechanisms than in young rats. The liver was found to be the most vulnerable to cold stress. It was concluded that fortifying the body by cold exposure is possible to use in old age, but with due regard to age-related restrictions.