NOVATO, California—Resistance training may reverse aging in skeletal muscle by altering mitochondrial function among health seniors, according to new research that appears online in Public Library of Science (PLoS).1

"The fact that their ‘genetic fingerprints' so dramatically reversed course gives credence to the value of exercise, not only as a means of improving health, but of reversing the aging process itself, which is an additional incentive to exercise as you get older."—Simon Melov, PhD.
"Our data strongly support the concept that mitochondrial dysfunction is associated with aging in humans," conclude the researchers led by Simon Melov, PhD, with the Buck Institute for Age Research, in Novato, California. "This implies that a functional improvement in aging muscle due to resistance exercise is associated with a global improvement in the molecular signature of aging, particularly for transcripts related to mitochondrial function."

Researchers analyzed gene expression profiles that involve age-specific mitochondrial function in tissue samples taken from the thigh muscles of 25 healthy older men and women who underwent 6 months of twice weekly resistance training. They compared the tissue samples to similar samples from younger healthy men and women. Participants were matched for diet and exercise. None of them took medication or had diseases that can alter mitochondrial function.

Mitochondrial function did, in fact, decline with age, but exercise training actually returned the mitochondrial function to levels similar to those seen in the younger adults. Before exercise training, the older adults were 59% weaker than the younger adults, but after 6 months of training the strength of the older adults improved by about 50%, such that they were only 38% weaker than the young adults.

The exercise training regimen used standard gym equipment. Men and women participated in twice-weekly, hourlong sessions comprising 30 contractions of each muscle group. The strength test was based on knee flexion.

In a 4-month follow-up, most of the older adults were no longer doing formal exercise in a gym, but most were doing resistance exercises at home.

Study authors "surprised"

 "We were very surprised by the results of the study," said Dr. Melov in a written press release. "We expected to see gene expressions that stayed fairly steady in the older adults. The fact that their ‘genetic fingerprints' so dramatically reversed course gives credence to the value of exercise, not only as a means of improving health, but of reversing the aging process itself, which is an additional incentive to exercise as you get older."


Exercise is the fountain of youth

"We have long known that exercise is the fountain of youth," said Lewis G. Maharam, MD, a sports medicine specialist in New York City. "The more we research the benefits of exercise, the more it solidifies what we have been thinking for years. People who don't exercise as they get older end up having more falls, osteoporosis, and hip fractures than people who are exercising all along," Dr. Maharam told CIAOMed.

Resistance exercise builds strong muscle and bone, but Dr. Maharam emphasized that any and all exercise that increases heart rate is good. "Walking 30 minutes at the mall every day is better than doing nothing," he said.

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Reference

1. Melov S, Tarnopolsky MA, Beckman K, et al. Resistance exercise reverses aging in human skeletal muscle. PLoS ONE. 2007;2(5):e465. doi:10.1371/journal.pone.0000465.