FAYETTEVILLE, Ark. (KNWA/KFTA) — A new study suggests that exercise, even if not adopted until later in life, can slow the effects of aging.

The paper was written by a team of seven researchers across three institutions, including Kevin Murach, an assistant professor in the Department of Health, Human Performance and Recreation at the University of Arkansas. Murach’s grant from the National Institute of Health funded the study, and he was one of three co-first authors.

The article, recently published in Aging Cell, is titled “Late-life exercise mitigates skeletal muscle epigenetic aging.”

While the paper is dense with data, reflecting the use of several analytic tools, the experiment that generated the data was relatively straightforward:

Lab mice nearing the end of their natural lifespan, at 22 months, were allowed access to a weighted exercise wheel. Generally, mice require no coercion to run and will do so voluntarily. Older mice will run anywhere from six to eight kilometers a day, mostly in spurts, while younger mice may run up to 10-12 kilometers. The weighted wheel ensured they built muscle. While there isn’t a direct analogue to most human exercise routines, Murach likened it to “a soldier carrying a heavy backpack many miles.” When the mice were studied after two months of progressive weighted wheel running, it was determined that they were the epigenetic age of mice eight weeks younger than sedentary mice of the same age — 24 months.

Methodology used in “Late-life exercise mitigates skeletal muscle epigenetic aging”

Murach noted that while the specific strain of mice and their housing conditions can impact lifespans, stating that “historically, they start dropping off after 24 months at a significant rate.”

The science behind this hinges largely on a biological process known as DNA methylation. A recent New York Times article discussing Murach’s work on muscle memory described methylation “as a process in which clusters of atoms, called methyl groups, attach themselves to the outside of genes like minuscule barnacles, making the genes more or less likely to turn on and produce particular proteins.”

Though the connection between methylation and aging is clear, the connection between methylation and muscle function is less clear. Murach is not yet prepared to say that the reversal of methylation with exercise is causative for improved muscle health.

“That’s not what the study was set up to do,” he explained. However, he intends to pursue future studies to determine if “changes in methylation result in altered muscle function.”

This is Murach’s fourth paper published as a faculty member of the U of A, where he arrived in June of 2021 and established the Molecular Muscle Mass Regulation Laboratory.