Navigation Links
Aerobic Exercise Helps Maintain Muscle in Elderly: Research

Why do older people tend to lose muscle mass and grow frail? One important factor identified by medical science is the reduced ability of the elderly to respond to the muscle-building stimulus of the hormone insulin.

Insulin is best known for its link to diabetes a condition in which either a complete lack of insulin or systemic resistance to the hormone's activity (as in type 2 diabetes) causes blood sugar levels to soar out of control. Recent studies have shown, however, that insulin also provides crucial assistance in building muscle, and that its ability to do so drops off dramatically in the elderly.

Now, a small but provocative study by medical researchers in Texas and California suggests that a simple, cost-free therapy appears to largely overcome that drop-off in insulin response: moderate aerobic exercise such as walking.

Experiments at the University of Texas Medical Branch at Galveston (UTMB) and the University of Southern California, Los Angeles conducted on 13 healthy volunteers in their late 60s showed that 45 minutes of walking 20 hours before exposure to insulin restored the muscle-growth-stimulating effects of the hormone to levels comparable to those seen in normal young adults.

Prior research had suggested that a large part of the problem older people experience lies in the tiny blood vessels that feed the muscles protein-building amino acids, glucose and insulin (which itself also works within muscle cells as a powerful protein growth factor). In young adults, these normally closed vessels open wide in response to the insulin increase generated by a meal, providing clear passage for muscle-making materials. In elderly people, however, this process, known as "vasodilation," is much less pronounced.

"We thought, let's see what happens if we use aerobic exercise, one of the interventions that has been shown in the past to improve vasodilation, to find out whether we can get insu lin to stimulate muscle synthesis in older people," said UTMB professor Elena Volpi, senior author of a paper on the experiments appearing in the June issue of the journal Diabetes. "It turned out that a fast walk restored the insulin response quite well."

To test their hypothesis, the researchers first required six of their 13 subjects to walk for 45 minutes on a treadmill quickly enough to keep their hearts beating at 70 percent of their maximum rate the same aerobic intensity level recommended to maintain cardiovascular fitness. The other seven subjects simply rested.

On the following morning, the researchers sampled the blood going into and coming out of thigh muscle in each of the volunteers, while supplying via the femoral artery a concentration of insulin similar to that released after a typical meal. They also took three small muscle tissue samples from each subject.

Tracer techniques enabled the scientists to track amino acids (the building blocks of muscle proteins) and determine muscle-protein synthesis and breakdown rates from the blood and muscle samples, while measuring blood flow at the same time. These revealed that the volunteers who exercised had both higher blood flow and net muscle protein growth. In addition, the researchers screened the muscle biopsy samples for signals associated with insulin's ability to stimulate the assembly of muscle protein from amino acids. This test also showed that exercise boosted insulin's role as a muscle protein growth factor.

"We already know that moderate aerobic exercise reduces cardiovascular disease, improves glucose uptake, and improves endurance," Volpi said. "Now it looks like it may also slow the rate of muscle loss in aging. We need to test this hypothesis further with larger trials, but still, it's one more reason why elderly people ought to be regularly walking, swimming or cycling."


Related medicine news :

1. Step Aerobics Increases good cholesterol
2. Aerobic Exercise Beneficial In Treating Depression
3. Aerobics- right choice for Cutting Blood Pressure
4. Ballroom Dancing A Good Aerobic Workout
5. Why Aerobic Exercise Is Good for the Heart
6. Aerobics Turn Enlarged Heart into a Trimmer, More Efficient Organ
7. Exercises reduce risks of cancers
8. Exercise lowers Risk of Ovarian Cancer
9. Exercise is necessary in daily life
10. Exercise for patients with cancer
11. Exercise therapy for fibromyalgia
Post Your Comments:

(Date:11/30/2015)... ... December 01, 2015 , ... The National Association of ... into its VIP Woman of the Year Circle. She is recognized with this ... exclusively for professional women, boasting 850,000 members and over 200 operating Local Chapters. ...
(Date:11/30/2015)... ... December 01, 2015 , ... ... carrier to offer individual vision insurance plans on . The multi-carrier ... to rate and review products, allowing consumers to compare, quote and match plans ...
(Date:11/30/2015)... ... November 30, 2015 , ... Stress, anxiety, illness, infection or ... worry about possible tumors? , Heather Spader, MD, a new pediatric neurosurgeon at Joe ... some signs might point to tumors. , “Bad headaches that don’t go ...
(Date:11/30/2015)... ... November 30, 2015 , ... MOSI recently added two ... along with Back to the Jurassic to their collection of interactive exhibits within the ... dynamic worlds that will allow guests to get closer than ever to a range ...
(Date:11/30/2015)... Creek, Michigan (PRWEB) , ... November 30, 2015 , ... ... MI, the American Cancer Society held an annual fundraising event, a 5K walk known ... a holistic treatment center for substance abuse which is also located in Battle Creek, ...
Breaking Medicine News(10 mins):
(Date:11/30/2015)... 2015  Kevin Smith has been appointed Chief ... pioneer in wireless monitoring of vital signs.  As ... , Mr. Smith will be responsible for the ... He will also directly oversee partnering with US ... for SensiumVitals, the first early warning detection device ...
(Date:11/30/2015)... 2015  PTS Diagnostics, the U.S.-based manufacturer of point-of-care ... A1CNow ® systems, and PTS Detect™ cotinine systems, ... that will propel the company into the mHealth market. ... Europe . The technology is a system that ... smartphones and tablets, and uses test strip technology already ...
(Date:11/30/2015)... Wash. and ST. LOUIS ... Express Scripts (NASDAQ: ESRX ) today announced an ... The partnership, which began in 1999, will now extend ... --> After evaluating pharmacy benefit manager ... concluded that Express Scripts continues to offer the best ...
Breaking Medicine Technology: