Health and Medical News and Resources

General interest items edited by Janice Flahiff

A blend of soy and dairy proteins promotes muscle protein synthesis when consumed after exercise

From the 24 January 2013 EurkAlert

A blend of proteins supplies amino acids to muscles and extends growth and repair

ST. LOUIS, Jan. 24, 2013 – A new study published in The Journal of Nutrition demonstrates the benefits of consuming a protein blend for muscle protein synthesis after exercise. This study is a first-of-its-kind, conducted by researchers at the University of Texas Medical Branch, and utilizes the proteins from soy, whey and casein consumed after an acute bout of resistance exercise. These proteins have complementary amino acid profiles and different digestion rates (amino acid release profiles). The results demonstrate prolonged delivery of amino acids to muscles and extended muscle protein synthesis when subjects consumed the blend, compared to a single source of protein alone.

“Sources of high-quality protein contain all the essential amino acids and have individual characteristics thought to offer a unique advantage for muscle growth,” said Blake Rasmussen, Ph.D., interim chair, Department of Nutrition & Metabolism and principal investigator of the study. “This is the first study to test the effects of combining soy with the dairy proteins, whey and casein, for promotion of lean body mass gain.”…

For more information on the study, the following is a link to the study on the Journal of Nutrition site. http://jn.nutrition.org/content/early/recent

Solae™ soy-based ingredient solutions help create nutritious, great-tasting products with a unique combination of functional, nutritional, economical and sustainable benefits. Solae, LLC, originally a DuPont joint venture, was fully acquired by DuPont on May 1, 2012, and is now part of DuPont Nutrition & Health, a world leader in specialty food ingredients. For more information, visitwww.Solae.com, or follow us on Twitter at www.Twitter.com/SolaeLLC, Facebook at www.Facebook.com/SolaeLLC, and LinkedIn at www.linkedin.com/company/Solae-LLC.

 

Read the entire article here

 

January 25, 2013 Posted by | Nutrition | , , | Leave a comment

Research debunks bodybuilding myth: Growth-promoting hormones don’t stimulate strength

Muscles!

Muscles! (Photo credit: Unlisted Sightings)

From the 14 June 2012 EurekAlert

New research from scientists at McMaster University reveals exercise-related testosterone and growth hormone do not play an influential role in building muscle after weightlifting, despite conventional wisdom suggesting otherwise.

The findings indicate that bodybuilders who look to manipulate those hormones through exercise routines are wasting their time.

In two separate studies, published in the Journal of Applied Physiology and the European Journal of Applied Physiology, researchers found anabolic hormones—long thought to be essential for building a muscular frame—do not influence muscle protein synthesis, the process that leads to bigger muscles.

“A popular mindset for weightlifters is that increased levels of hormones after exercise play a key role in building muscle,” explains Daniel West, lead author of both studies and a graduate student in the Department of Kinesiology at McMaster. “That is simply not the case.”

In the first study, researchers examined the responses of both male and female participants to intense leg exercise. Despite a 45-fold difference in testosterone increase, men and women were able to make new muscle protein at exactly the same rate.

“Since new muscle proteins eventually add up to muscle growth, this is an important finding,” says West.

“While testosterone is definitely anabolic and promotes muscle growth in men and women at high doses, such as those used during steroid abuse, our findings show that naturally occurring levels of testosterone do not influence the rate of muscle protein synthesis.”

In the second study, researchers analyzed the post-exercise hormonal responses of 56 young men, aged 18 to 30, who trained five days a week for 12 weeks in total.

The men experienced gains in muscle mass that ranged from virtually nothing to more than 12 pounds, yet their levels of testosterone and growth hormone after exercise showed no relationship to muscle growth or strength gain.

Surprisingly, the researchers noted that cortisol—considered to have the opposite effect of anabolic hormones because it reduces protein synthesis and breaks down tissue—was related to the gain in muscle mass.

“The idea that you can or should base entire exercise training programs on trying to manipulate testosterone or growth hormone levels is false,” says Stuart Phillips, a professor in the Department of Kinesiology. “There is simply no evidence to support this concept.”

 

June 15, 2012 Posted by | Medical and Health Research News | , , , , , , | Leave a comment

Weight Regain After Loss Potentially Dangerous for Postmenopausal Women

From the Wake Forest Baptist Medical Center 12 December 2011 press release

…shedding the pounds may have some negative consequences on the overall health of older women if the weight loss is not maintained, according to a new study by researchers at Wake Forest Baptist Medical Center.

Published recently in the American Journal of Clinical Nutrition, the study showed that some older women who lose weight gain a lot of their weight back within a year. Importantly, the weight regained is mostly in the form of fat, rather than muscle.

“The body composition of some of the women was worse than before their weight loss,” said Barbara Nicklas, Ph.D., a gerontologist at the J. Paul Sticht Center on Aging and Rehabilitation at Wake Forest Baptist and principal investigator for the study. “When older women lose weight, they also lose lean mass. Most women will gain a lot of the weight back, but the majority of the weight regained is fat.”…

 

“Most people will regain their weight after they lose it.” Nicklas said. “Young people tend to regain weight in the proportion that they lost it. But the older women in our study did not appear to be regaining the muscle that they lost during initial weight loss in the same way.”

The long term consequences of losing muscle mass in middle aged and older women is yet unknown, but in combination with the loss in bone density known to occur as we age, the loss of muscle could increase their fall risk, among other things.

“There are certainly a lot of health benefits to weight loss, if you can keep the weight off,” Nicklas said. “For older women who lose weight, however, it is particularly important that they keep the weight off and continue to eat protein and stay physically active so that, if the weight does come back, it will be regained as muscle instead of fat.”

She cautioned that the results from this study were limited to sedentary, abdominally obese, postmenopausal women, and the findings may differ in men or in younger populations….

Read the entire press release

December 29, 2011 Posted by | Consumer Health, Nutrition | , , , | Leave a comment

   

%d bloggers like this: