Outmuscling sarcopenia

Sarcopenia, the loss of skeletal muscle mass that accompanies aging, is an inevitability for most people, but the severity of muscle loss varies.  

“Starting at age 40, adults can lose up to 8 percent of their muscle mass per decade. This rate can double by the age of 70,” said Suzette Pereira, research scientist at Abbott, a leader in nutrition science behind brands that include Pedialyte®, Ensure® and PediaSure®, among others. “The good news is, age-related muscle loss can be prevented or reversed with exercise and proper nutrition, including protein.”

Maintaining proper exercise is surprisingly not the biggest struggle for older adults.

“Many don’t know that as you get older, your body requires more protein to maintain muscle, yet research from Abbott and The Ohio State University using National Health and Nutrition Examination Survey [NHANES] data shows more than one in three adults over the age of 50 still aren’t getting the protein they need daily.”1

Abbott offers Ensure® nutrition drinks with protein and nutrients to help adults rebuild or maintain muscle for strength and energy. Additionally, they’ve introduced Ensure® Enlive—a specialized oral nutrition supplement containing muscle-specific ingredients.

A review published in Annals of Medicine and supported by Abbott confirmed the critical role muscle mass plays in health, with studies demonstrating that people with less muscle had more surgical and post-operative complications, longer hospital stays, lower physical function, poorer quality of life and overall lower survival.²

HMB

“While protein will always be critical for muscle health since it provides the building blocks for muscle, one ingredient that has been extensively studied is HMB, also known as beta-hydroxy-beta-methyl butyrate,” Pereira explained. “HMB has been used by the fitness community for decades, but research shows it also helps adults who want to maintain their muscle or are recovering from muscle loss following illness, injury or surgery. HMB reduces muscle breakdown, especially when your body is under stress—like from an illness or injury—that leads to muscle loss.”

HMB, a leucine metabolite, has been found to be capable of attenuating muscle decline in healthy older adults during complete bed rest.³

While the body produces HMB when it breaks down the amino acid leucine found in protein-rich foods, it is hard to maintain the right level of HMB because we make less of it with age, and common foods only contain small amounts of HMB (e.g., a consumer would have to eat more than 6,000 avocados or 110 eggs to get enough).

 “Most foods contain trace amounts of HMB, with meats being the premier source,” said Larry Kolb, president, TSI USA Inc. “While some vegetables such as asparagus and squash, or even herbal tea contain comparable amounts of HMB, the average concentration in fruits and vegetables is approximately five-fold lower. Endogenous production of HMB via transamination of leucine to alpha-ketoisocaproic acid (KIC), which is then oxidized to HMB, occurs in the muscle and liver, with 5 percent of leucine being converted into HMB.”  

Fortunately, HMB is found in high-protein nutrition drinks, which can supplement the diet.

 A 2016 study published in Clinical Nutrition found that Ensure® Enlive, a high -protein drink containing HMB, was associated with a 50-percent lower death rate in older malnourished patients with heart or lung disease 90 days following hospitalization.⁴ It also reported improved odds of better nutritional status at day 90 and an increase in body weight at day 30.

Leucine

Leucine is a branched-chain amino acid (BCAA) critical to hemoglobin formation. It’s also one of the nine essential amino acids in humans that’s provided by food.

“Leucine is a key activator of muscle protein synthesis (MPS) via activation of the mTOR pathway,” said Mayuresh Bedekar, global product manager at Glanbia Nutritionals. “Glanbia has done research looking at the role of its PepForm BCAA product, which is a leucine-rich whey peptide, in the muscular health of the elderly.”

With an oxidation rate higher than that of isoleucine and valine, leucine stimulates MPS and is closely associated with the release of gluconeogenic precursors. In skeletal muscle, there is a decrease in leucine level and a reduction in glycogen stores during exhaustive aerobic exercise.⁵  

In a 2015 study published in The Journal of Physiology, extended high-intensity resistance training following usual care after hip fracture was shown to improve muscle strength and physical function.⁶ Researchers noted the protein supplement leucine provided to participants following each exercise session might have served as an important rehabilitation adjunct to maximize muscle gains in this venerable population.

In the study, older individuals who participated in rehabilitation following bed rest, as defined by eccentric resistance training programs (combined with BCAA-enriched protein supplementation, as PepForm), reversed muscle functional deficits and restored muscle nutrient anabolic sensitivity to pre-bed rest levels.

According to Glanbia, the PepForm technology provides much higher levels of soluble and bioavailable amino acids that are linked to whey peptide.

Since most plant proteins have lower levels of leucine, it is suggested to use blends of different vegan proteins to reach the desired amino acid profile.

Astaxanthin

Natural astaxanthin from the microalgae Haematococcus pluvialis is a carotenoid found in arctic marine environments as well as common fresh water rock pools.  Lower levels of astaxanthin are also found in marine animals, such as krill, that eat the microalgae.

The AstaReal Group, a pioneer in the field of natural astaxanthin, recently announced the results of a randomized, double-blind, placebo-controlled study on the effectiveness of a new medical protocol to improve muscular function.⁷ Published in the Journal of Cachexia, Sarcopenia and Muscle, the study investigated the restoration of muscle loss and improvement of functional decline in elderly people with sarcopenia.

The four-month study focused on individuals aged 65 to 82 who took either natural astaxanthin (as AstaMed MYO™, from AstaReal) or placebo, and undertook an interval exercise training protocol. Over a four-month span, treatment recipients experienced a 40-percent increase in endurance, a 14 percent increase in muscle strength and an 8 percent increase in mobility, compared to no muscle strength improvement in those taking placebo.

“We saw improvements in strength, endurance and mobility among the study participants who took astaxanthin medicinal formula with a moderate exercise plan,” said lead researcher Kevin Conley, professor of radiology, University of Washington School of Medicine. “This gives clinicians an option for their patients who cannot make the substantial lifestyle changes required to halt the crippling impact of muscle loss.”

L-carnitine

L-carnitine is a naturally occurring derivate of the amino acid lysine. It is commonly involved in the metabolism of most mammals and may help protect muscle.

In a study published in the American Journal of Physiology L-carnitine tartrate (as Carnipure®, from Lonza) was shown to help reduce oxidative stress resulting from exercise, as well as muscle tissue soreness.⁸

“This provides a potential mechanism for reduced hypoxic stress, particularly following resistance exercise,” said Juliana Erickson, senior marketing manager, Lonza Consumer Health & Nutrition. “Recently, Lonza sponsored a trial showing that a new formulation of Carnipure® L-Carnitine along with creatine and leucine increased lean muscle mass and strength among subjects between 55 to 75 years old.”⁹

Green tea extract

A pre-clinical study sponsored by Abbott examined the ability of the green tea catechin, epigallocatechin-3-gallate (EGCG), to impact muscle mass and the molecular pathway involved in muscle atrophy in an animal model of sarcopenia. ¹⁰ The study concluded that a specialized green tea extract with high levels of antioxidant polyphenols can preserve muscle mass and function in animals undergoing age-related muscle loss.

Even though green tea extract has shown to positively correlate with muscle performance, muscle recovery is still an issue. In a 2015 study published in the Journal of Applied Physiology, researchers studied how green tea extract would improve muscle recovery after reloading following disuse.¹¹ The results suggested that while satellite cell proliferation and differentiation are critical for muscle repair to occur, green tea-induced changes in satellite cell number is, by itself, insufficient to improve muscle recovery following a period of atrophy in old rats.

Where is muscle support going?

“Sarcopenia is a world pandemic, especially affecting the Western world and other developed countries, such as Japan and South Korea due to the growing elderly population,”¹² Bedekar said. “They call it the inverted population pyramid, where a majority of the population is over 60 years old and is supported by a smaller group of working adults.”

Bedekar noted sarcopenia affects 50 million people today and will affect over 200 million in the next 40 years. “The estimated U.S. healthcare cost of sarcopenia equates to roughly US$900 per person per year,” he added. “All this presents a significant opportunity to nutrition companies who are looking to launch products in this healthy aging category.”

Manufacturers are clearly taking advantage of ingredient diversity by funding sarcopenia and muscle support research that could potentially be game-changing for older adults across the globe. Although, with an increasingly knowledgeable consumer-base, manufacturers are going to need to apply everything they’ve learned in the packaging space to effectively combat sarcopenia.  

“The boom of the sports nutrition market in recent years has also increased the demand for new and innovative supplements that support muscle health, meaning that manufacturers must adapt to meet this ever-growing variety of consumer preferences and remain competitive in a fast-paced market,” Erickson said. “With packed shelves and numerous choices available to consumers, manufacturers need to differentiate—for example, using robust scientific proof, innovative dosage forms or even visually on capsules or packaging.”

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