While you may not be a bodybuilder or serious athlete, your muscles are important for a long and healthy life. How you take care of them may determine your eventual fate as you age. Besides avoiding an older adulthood of frailty, muscles do more than we might think. They enhance metabolism, improve insulin sensitivity, and protect against type 2 diabetes. Strong muscles are fueled by consuming quality dietary protein along with strength (resistance) training and adequate calorie consumption.
As we flock to the gym post-holiday, New Year’s resolutions in tow, we should focus our efforts more on health than vanity as we seek to get into shape, whether that be shedding a few pounds and/or increasing our physical activity. Just eating less food to lose weight or doing any random exercise, however, may not help you achieve the benefits you want when it comes to building muscle. What we eat and how we train ensures we do not lose strength and muscle in the process.
To achieve optimal improvements in muscle mass and strength, a balanced program of strength training and a diet packed with quality protein are required. Strength training really deserves its own article, so here for the sake of space and simplicity, let us tackle protein.
Historically, an obsession with dietary protein intake was mostly the domain of weight lifters. For the rest of us, the subject was confusing and filled with contradictory information around frequent questions such as: how much protein do we need, what kind of protein should we choose, and when should we eat it? The answers impact our overall training results, health, and longevity.
Protein supports many functions in the body, particularly the building and maintenance of muscle, which we can, without intervention and determination, slowly lose as we age. But if you are not in older adulthood yet, why be concerned now? The bad news is that loss of skeletal muscle starts early and happens slowly and without our noticing. It pays to be preemptive and start with a good baseline. “Beginning around age 50, we can lose up to 1% of our muscle mass as well as a loss of strength up to 3% annually.
Without strength training intervention, this pace can accelerate to a 4% loss of strength annually by age 75.” Too, extended bedrest due to a temporary illness, injury, or hospitalization may accelerate muscle loss, even in younger individuals, in as little as two to three weeks (although younger adults recover and regain muscle much better). This is yet another reason to build muscle reserves—think of it as a muscle savings account.
Why Does Muscle Mass Matter?
Losing too much muscle mass eventually results in frailty and a condition known as sarcopenia, defined as the gradual and progressive loss of muscle mass, strength, and function. Avoiding a future of frailty should provide a strong motivator as this condition can lead to suffering and take a toll on your future quality of life (and, in aggregate, our society as a whole).
The mortality rate of older adults with sarcopenia is 41% higher than those without sarcopenia (Koon Yee-Lee et al. 2021)—not to mention their disability and suffering—and the estimated cost of just hospitalizations in the U.S.in individuals with sarcopenia was estimated at $40.4 billion. (Goates et al. 2019). There are currently no recommended drug treatments for sarcopenia.
According to an article and study published in the American Journal of Nutrition that pooled data from 16,155 individuals aged 20 to 93, “Increased muscle mass is associated with a 30% reduction in early mortality risk.”
Why is It Harder to Build and Maintain Muscle Mass as We Age?
As we age, we have what is called reduced anabolic resistance to protein intake versus when we were younger, making it harder for us to build muscle from protein. In other words, we are not able to utilize the protein we eat to build muscle as well as when we were younger. Authors Paulussen, McKenna, and Beals in NIH Frontiers in Nutrition describe it physiologically as “a blunted stimulation of muscle protein synthesis rates (MPS) to common anabolic stimuli in skeletal muscle tissue such as dietary protein and exercise.
Ultimately, the blunted responsiveness of MPS to dietary protein and exercise underpins the loss of the amount and quality of skeletal muscle mass leading to decrements in physical performance.”
How Much Protein Do We Need?
Many of us do not get enough protein due to a variety of reasons. Older individuals may experience a loss of taste and smell (which can decline with age), influencing appetite,Too, motivation to cook and pay attention to daily diet requirements often decreases for those of all ages who live alone.
Then, there is the easy convenience of take-out and processed food which is frequently filled with empty calories. Hectic schedules and busy careers leave little time to prepare meals from scratch. And weight loss diets sometimes do not provide enough protein to prevent muscle wasting while shedding pounds.
So, how much protein do we need? A study conducted by Traylor, Gorissen, and Phillips published in Advances in Nutrition cited “the Dietary Reference Intakes set the protein RDA (recommended daily allowance) for persons older than 19 y[ears] of age at 0.8 g[rams] protein per [kilogram] (or 0.36 grams per pound) of body weight.” (One kilogram (kg) equals 2.2 pounds, and converters are online).
However, a growing body of evidence suggests, that this protein RDA may be inadequate for older individuals.” Some think reduced anabolic resistance in older adults suggests they may need “up to double the amount of protein in a single meal” than younger adults do.
Even in younger individuals, some experts view the standard RDA as inadequate, suggesting that “1.2-1.6 grams of protein per [kilogram] of body weight daily (or 0.54.-0.72 grams per pound.)” is more appropriate.
While “evenly distributing protein across meals may be ideal, (20-25 g[rams] of high-quality protein per meal; 20-30 g[rams] for older adults),” recent studies show even consuming a large amount to protein such as “100 grams after exercise elicited a robust and prolonged anabolic response.” Historically, there has been “an assumption the body cannot use more than 20-25 grams at a time.” The net-net here is that “total daily protein is more critical than precise distribution.”
Critically, “the often-cited potential negative effects of consuming higher protein intakes on renal and bone health are without a conclusive scientific foundation in healthy humans without pre-existing kidney disease.”
What Kind of Protein Should We Eat?
When selecting protein foods, factors like digestibility, plant or animal-protein, and amino acid composition (complete versus incomplete) are considerations and determine a protein’s quality.
Amino acids are the building blocks of protein. There are 20 our bodies need in all. Eleven are called nonessential amino acids because we can make them ourselves. The other nine must be obtained from food, and these are called essential amino acids. You may have heard food protein being categorized as “complete proteins” (contains all the essential amino acids) versus “incomplete proteins” (contains some but not all the essential amino acids).
Animal proteins (including eggs and dairy) contain a complete amino acid protein combination, providing all the essential amino acids. Plant proteins (except for tofu, edamame, tempeh, and miso), on the other hand, tend to be incomplete, so a larger quantity and diversification of total protein sources are needed to achieve complementary amino acid profiles (protein combining) to get all nine essential amino acids.
Vegans must eat a variety of legumes, nuts seeds, whole grains, and vegetables during the day to balance complementary amino acid profiles to obtain the required essential amino acids. Also, “supplementing with plant-based protein isolates or concentrates” may help vegans and vegetarians reach their protein goals. Supplementing with whey may be “particularly effective in stimulating MPS and casein offers a prolonged release of amino acids that sustain MPS over time.”
The study by Traylor, Gorissen, and Phillips further proposed “that it should be recommended that older individuals place an emphasis on the intake of the amino acid leucine, which plays a central role in stimulating skeletal muscle anabolism.”
Katsanos et al. showed “that a mixture of all EEAs (essential amino acids) with leucine content at 1.7 g[rams] stimulated MPS (muscle protein synthesis) in younger adults; however, this response was not observed in the older adults. When leucine content was increased to 2.8 g[rams] there was an observed increase in MPS rates in the older adults.”
While leucine triggers this process, “all essential amino acids are needed to sustain MPS for four to six hours,” hence the importance of a balanced diet with adequate quality protein intake.
When Should We Eat Protein?
Recent studies have shown “no meaningful difference between pre- and post-exercise protein intake.” In fact, the anabolic window once thought to be limited to a 30-minute to 2-hour post-exercise period where muscle protein synthesis is elevated, research now indicates that muscle protein synthesis “remains significantly heightened for up to 24 hours after exercise.”
Exercise and Protein: A Dynamic Duo
While a sedentary lifestyle exacerbates anabolic resistance, the good news is exercise does just the opposite. One study showed “older adults can even achieve the muscle anabolic response of younger individuals when protein is consumed after exercise.”
Some longevity experts believe high protein diets lead to accelerated aging and cancer. However, this is unfounded in studies with healthy humans. A high protein diet, when combined with exercise, “directs growth factors (like IGF-1) and proteins (like mTOR) toward beneficial functions” rather than nonbeneficial ones like “promoting the survival of precancerous cells potentially raising cancer risk. Exercise fundamentally alters how IGF-1 behaves in the body.”
Exercise and a quality protein diet go hand in hand.
Conclusion
When checking off those 2025 New Year’s resolutions, make a goal of building and keeping your muscles in good shape. Your future self will thank you. Wishing you a healthy and active aging journey!
Note: Nothing in this article is meant to provide medical advice or personal dietary recommendations. Please consult your medical health care professional before beginning any new exercise or dietary program.
Lydia is a passionate advocate of healthy living. She has launched and positioned many health and wellness-related companies, products, technologies and organizations receiving more than 100 awards nationally and internationally. Her focus in the health sector is specifically on healthy living, aging and longevity. She is a partner and investor in several recognized national brands. She sits on the board of the Buck Institute for Research on Aging whose mission is to eliminate the threat of age-related disease for today’s and future generations. It is the only independent research organization globally dedicated to extending the healthy years of life. Like the scientists at the Buck, Graham envisions it will be possible for people to enjoy life at 95 as much as at 25. To support Buck’s mission, please visit www.buckinstitute.org.