Aged skin and strenuous exercise: Can the skin handle the heat?

As the number of older adults participating in strenuous exercise and sports increases, there exists a need to understand the effect of ageing on thermoregulation during strenuous exercise. The question of whether age affects the capacity to disperse heat to the external environment has been studied with equivocal results. Most researchers agree that skin blood flow is diminished with age due to central and peripheral vasodilatory mechanisms. In the skin this can include vascular stiffness and decreased activity and sensitivity to vasodilators. Additionally, other studies have also proposed that due to a reduction in the output of individual sweat glands there is a diminished sweating response with increasing age. However, where thermoregulatory differences in older adults have been observed, the response of the older subjects can be likened to the response seen in untrained younger adults. It is difficult to differentiate between thermoregulatory differences due to age-related cardiovascular changes, age-related lifestyle changes, and potential age-related alterations to skin blood flow and sweat gland function. The testing of trained adults in different age groups would alleviate lifestyle differences as trained subjects approach their genetic potential for undertaking physical work with less apparent physiological strain. Future research should be aimed at comparing the effect of habitual physical activity and ageing on the response to exercise-heat stress, passive heat stress or chemically induced skin blood flow and sweating responses. This will allow future researchers to accurately describe the effect of aging on thermoregulation and if there are any additional risks for older adults participating in strenuous exercise and competition.