a recent study<\/a> from Tufts University published in the American Journal of Clinical Nutrition shows that protein alone doesn\u2019t equate to muscle strength.<\/p>\nIn fact, as long as they\u2019re getting the normal recommended amount of protein in their diets to begin with (as most older people in the U.S. do), older adults are better off hitting the gym if they want to keep their muscles youthful, said lead author and endocrinologist Lisa Ceglia, an associate professor at Tufts University School of Medicine and a postdoctoral fellow at the Jean Mayer USDA Human Nutrition Center on Research Center on Aging (HNRCA), who worked on the study with colleagues including HNRCA Senior Scientist and School of Medicine Professor Bess Dawson-Hughes.<\/p>\n
A slow decline<\/p>\n
The slow decline of muscle strength starts around age 40, when the kidneys begin to lose the ability to excrete acid from the body effectively. The body starts breaking down muscle to release basic substances that neutralize the acid, like baking soda neutralizes vinegar.<\/p>\n
Past studies have come tantalizingly close to showing that adding protein to an older person\u2019s diet can curb muscle loss \u2014 they\u2019ve shown that it increases the growth factors that kickstart the process, and that protein in conjunction with exercise builds strength.<\/p>\n
But until recently, scientists had stopped short of rigorously testing whether extra protein alone can limit muscle loss in a person who\u2019s healthy and well nourished. \u201cSo then you start to say, yes, in theory this makes a lot of sense, but let\u2019s look at the reality,\u201d Ceglia said.<\/p>\n
To test the benefits of protein alone, she and her collaborators recruited 141 study participants\u2014all people aged 65 and above from the greater Boston area\u2014and assigned some of them to take capsules containing whey powder while others took a placebo control. Made from milk, whey is rich in an amino acid called leucine, which is particularly good at jumpstarting the cellular pathways that build muscle. Other types of protein supplements (such as soy) might have different effects, but the researchers deemed whey the most likely to lead to muscle growth.<\/p>\n
Along with whey powder, the researchers gave participants potassium bicarbonate, a component of antacid tablets. If acid build-up was the reason for loss of strength, they figured neutralizing the acid via the potassium bicarbonate could let muscles recover. Smaller studies had suggested they might be right.<\/p>\n
After 24 weeks, the researchers tested the study participants\u2019 strength with a range of exercises, from leg presses to a balance test. The results were unexpected: Participants\u2019 strength was unchanged by the extra protein, with or without potassium bicarbonate. Those results were the same regardless of participants\u2019 sex.<\/p>\n
\u201cWe were surprised,\u201d Ceglia said, especially because tests revealed that the participants\u2019 bodies were primed to make more muscle. They excreted more acid, as a younger person would, and they had elevated levels of a muscle building hormone called IGF-1.<\/p>\n
Open questions<\/p>\n
So why didn\u2019t they build more muscle? \u201cThis is an excellent question, and one that I\u2019ve been asking myself,\u201d Ceglia said. It\u2019s possible that the study participants\u2019 muscles were undergoing subtle changes that the strength tests weren\u2019t sensitive enough to pick up. It\u2019s also possible that without added exercise, participants\u2019 bodies didn\u2019t know what to do with the extra protein.<\/p>\n
People who\u2019ve recently added more exercise into their routines might benefit from protein supplementation. Other groups, such as those who become malnourished after serious injuries like hip fractures, may benefit too. This is why the protein-rich drink Boost is sometimes prescribed to people who have poor appetite after surgery.<\/p>\n
\u201cBut if you\u2019re just a healthy individual living in the community and eating protein at the recommended daily amount, there\u2019s no evidence that protein supplementation alone will have a huge impact on your strength and function,\u201d Ceglia said.<\/p>\n
In the future, Ceglia would like to investigate the combination of exercise and protein supplementation to see if the two together are more effective than exercise alone. Until then, she recommends that older people use resistance training to keep their strength up. \u201cIt\u2019s the most consistently effective option we have for improving strength and function,\u201d she said.<\/p>\n","protected":false},"excerpt":{"rendered":"Packing in the protein is all the rage. From cereal to pasta to nacho chips and more, food…\n","protected":false},"author":2,"featured_media":949022,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4318],"tags":[105,4434,16,15],"class_list":{"0":"post-949021","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-nutrition","8":"tag-health","9":"tag-nutrition","10":"tag-uk","11":"tag-united-kingdom"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@uk\/116546529718786950","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/949021","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/comments?post=949021"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/949021\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media\/949022"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media?parent=949021"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/categories?post=949021"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/tags?post=949021"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}