Acute influence of mild cycle exercise on cold sensory function in young women with awareness of cold constitution

In order to clarify the acute effects of exercise on the cold sensory function of cold-sensitive women, 12 young adult females with an awareness of cold constitution were subjected to two experiments: an exercise condition in which cycle exercise with a light-to-moderate intensity for 15 min was performed and a control condition in which rest without exercise was maintained in a crossover design. Cooling tests in which the hand was immersed in cool water at 15°C for 1 min were carried out before exercise, immediately after exercise, and 30 min after exercise, and the sensitivity of the cold sensory function was evaluated based on changes in skin temperature, thermal sensation, and comfort in the hand. In the control condition, cooling tests were performed at the same timing as in the exercise condition. Cold sensation and thermal discomfort during hand cooling were reduced by a significant increase (+0.5 ± 0.3°C) in core body temperature after exercise. Exercise did not alter the sensitivity of thermal sensation, but reduced the sensitivity of thermal comfort. These sensitivities remained unchanged throughout the control condition. A warm feeling increased in the trunk portion immediately after exercise, but a cold feeling in the foot decreased at 30 min after exercise. This suggested that the thermal sensation was affected in a site-dependent manner due to increases in core and skin temperatures after exercise, and that the sensitivity of cold-induced discomfort is transiently suppressed without altering the sensitivity of cold sensation.