Why does aging make you thin? Can you prevent it?
As people get older, their arms and legs become thinner, making them weak with more chances for falls and fractures. Research is now showing why this is happening and how to handle it.
Researchers from Nottingham have been researching about this and had already shown that the food intake by the elderly cannot convert to muscles as fast as in their younger counter parts. Newer research by the same team, has now found that the suppression of muscle breakdown, which also happens during feeding, is blunted with age. They belive that a ‘double whammy’ affects people aged over 65. However the team think that weight training may “rejuvenate” muscle blood flow and help retain muscle for older people.
When they eat they don’t build enough muscle with the protein in food; also, the insulin fails to shut down the muscle breakdown that rises between meals and overnight. Normally, in young people, insulin acts to slow muscle breakdown. Common to these problems may be a failure to deliver nutrients and hormones to muscle because of a poorer blood supply.
Research just published in The American Journal of Clinical Nutrition compared one group of people in their late 60s to a group of 25-year-olds, with equal numbers of men and women. Professor Rennie said “We studied our subjects first — before breakfast — and then after giving them a small amount of insulin to raise the hormone to what they would be if they had eaten breakfast, of a bowl of cornflakes or a croissant. We tagged one of the amino acids (from which proteins are made) so that we could discover how much protein in leg muscle was being broken down. We then compared how much amino acid was delivered to the leg and how much was leaving it, by analysing blood in the two situations. The results were clear. The younger people’s muscles were able to use insulin we gave to stop the muscle breakdown, which had increased during the night. The muscles in the older people could not.” In the course of our tests, we also noticed that the blood flow in the leg was greater in the younger people than the older ones . This set us thinking: maybe the rate of supply of nutrients and hormones is lower in the older people? This could explain the wasting we see.”
Another researcher Beth Philips confirmed the blunting effect of age on leg blood flow after feeding, with and without exercise. The team predicted that weight training would reduce this blunting. “Indeed, she found that three sessions a week over 20 weeks ‘rejuvenated’ the leg blood flow responses of the older people. They became identical to those in the young,” said Professor Rennie.
Source: University of Nottingham
Image Credit: Flickr
