Health & Wellness

Exercise Seems to Keep the Immune System Young

A British study suggests that regular cycling can ward off some of the effects of aging

By Wendy Haaf

Regular exercise may be the next best thing to a fountain of youth for your immune system, a British study hints.

Researchers at the University of Birmingham and King’s College London compared several different measures of immune function in three groups: very fit long-time cyclists aged between 55 and 79; age-matched inactive adults; and healthy adults aged 20 to 36 who weren’t regular exercisers.

In most people, around age 20, the thymus gland begins shrinking and starts turning out fewer T cells, a type of immune cell involved in a host of functions, including regulating immune reactions and destroying cancer cells and infected cells. (Produced in bone marrow, T cells mature and develop into subtypes in the thymus gland.) Compared with their same-age peers, cyclists’ blood contained higher levels of a hormone that protects the thymus, and greater numbers of various immune cells that prevent harmful immune reactions. In fact, the cyclists were churning out T cells in numbers nearly identical to those found in the younger participants.

In addition, the long-time exercisers showed none of the decline in muscle mass or strength usually associated with aging.

The study results were published in Aging Cell, the peer-reviewed journal of Britain’s Anatomical Society.

Photo: iStock/Steve Debenport.