"It is not a mystery that exercise and nutrition help slow the aging process," said Benjamin F. Miller, Ph.D., a researcher involved in the work from the Department of Health and Exercise Science at Colorado State University in Fort Collins, Colorado. "Studies such as ours help to explain how exercise and nutrition work so that we can better take advantage of those pathways to slow the aging process."
To make this discovery, scientists recruited 16 participants age 37 and older and instructed them to exercise on treadmills for 45 minutes three times a week for six weeks. After each bout of exercise, one group was given a protein drink and another group was given a carbohydrate drink. To measure the making of new structures in the muscle, metabolic pathways were measured using heavy water labeling. Subjects consumed heavy water, which becomes incorporated into many synthetic processes allowing measurement of the rates at which different components of the muscle are being made. Using ultra-sensitive mass spectrometry methods, scientists took muscle samples at the end of the six weeks and were able to determine how much of the muscle and its component pieces were new. In this case, new proteins, DNA, and membranes were measured. This showed that endurance exercise, commonly prescribed for older people for a healthful lifestyle, induces positive changes in skeletal muscle structure.
"If you want to age gracefully, this study shows that proteins taken after exercise keep your muscles strong and fit," Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal
. "You've got to feed your body with the proper nutrients after a work-out. Fortunately, protein shakes are cheap, readily available and some say taste good."