That Americans today report sitting for an average of more than 9 hours a day, despite all we know about how harmful this can be, is a true testament to the universal instinct to kick the can down the line when it comes to personal health.
Mountains of evidence tell us that an overly sedentary lifestyle can take a toll on the heart and brain and can elevate cancer risk. A 2024 JAMA study of nearly a half-million people over a dozen years found that sitting most of the day at work leads to a 16% higher risk for early death.
But hey, these are all longer-term dangers and are both tempting and easy to ignore when faced with the immediacy of the deadlines, meetings, emails, and doomscrolling that can keep us glued to chairs and sofas for hours at a time.
As research has begun to look more closely at the mechanisms causing some of the more well-documented effects of prolonged sitting, newer findings connecting certain movement patterns to the body’s ability to build muscle provide a compelling reason to get up and move.
One element making get-up-and-move logic truly work often gets short shrift in relation to all the other recs about physical activity and long periods of sitting: Protein synthesis.
Lack of Movement Overshadows Lack of Fuel
Daniel Moore, PhD, associate professor in muscle physiology at the University of Toronto in Toronto, Ontario, Canada, jokes that he essentially studies an old adage: Use it or lose it.
In 2022, Moore published the first study on prolonged sitting and amino acid utilization, in which he found that taking regular, short walking or squatting breaks in the hours after eating improved the body’s ability to turn dietary proteins into the building blocks of muscle. Though his results were based on a small group of just 12 people, the effect was consistent and large, and also lines up with 2019 findings that showed a 27% decrease in this muscle fueling when people were forced to reduce their daily steps by 90%.
Plenty of previous attempts to understand the more immediate effects of sitting have focused on diet and metabolism, or the body’s ability under different conditions to utilize what we fuel it with, explained Janice Thompson, PhD, emeritus honorary professor of public health, nutrition, and exercise at the University of Birmingham, Birmingham, England, who wasn’t involved with Moore’s study. It’s just that protein never gets the spotlight over carbohydrates and fats.
Of the three major macronutrients, “we predominantly use protein for building and repair,” said Thompson. “That’s its primary purpose, whereas carbohydrates and fats predominantly provide us with energy.” Because of this, carbohydrates and fats play significant roles in controlling blood sugar levels, which makes them key catalysts for the sort of later-in-life cardiovascular issues tied to sitting (and therefore key research targets).
Even so, said Thompson, proteins represent “an exciting other piece of the puzzle,” in the interconnected story of metabolic health. Research like Moore’s is essential to completing the big picture.
In fact, parts of Moore’s findings closely mirror what other researchers have found about the importance of muscle movement itself in metabolic output. Previous studies on glycemic control have found that “any sort of muscle contraction has what we call an insulin-like effect,” said Thompson. “There’s something about that muscle contraction that’s quite critical.”
That something is the control of blood flow throughout the body. If blood vessels are like the train tracks on which nutrients and other tools navigate the body to ensure every worksite has all the supplies it needs to go without breaks, muscles are the steam-powered engines, keeping everything moving as long as they are. This also means that standing, unfortunately, just won’t cut it as a helpful intervention for any of the harmful metabolic effects of sitting.
In the End, You Have to Build Muscle
Building muscle isn’t just for bodybuilders, explained Stuart Phillips, PhD, professor of kinesiology and the director of the Physical Activity Centre of Excellence at McMaster University in Hamilton, Ontario, Canada, who wasn’t involved with Moore’s study. Protein synthesis, the final stage of the process that transforms what we ingest into muscle mass, is an ongoing necessity as damaged proteins are flushed from the same muscles. This turnover process is essential for everyday muscle function, but “to drive it and store protein, you have to do some form of movement,” said Phillips.
So how much movement is enough? The answer, according to Moore and Phillips, isn’t so simple. The last few years of exercise science have ultimately taught us that “it’s not just about how much we move during the day, but when we move,” said Moore. That’s why he and others who study movement patterns most often recommend what are now widely called “activity snacks,” short yet regular bursts of movement throughout the day that successfully counteract the effects of sitting (yep, they boost cardiovascular health, too).
But not all snacktivity — a word right from the literature — is created equal. In Moore’s study, which looked at twice-hourly breaks of either a 2-minute walk or 15 squats, the squats activated an additional biological pathway for protein synthesis that wasn’t present in the walkers.
It’s possible, he said, that this reflects the enhanced benefits of resistance exercise compared to everyday movements, which the body may be more used to. Other, creative ways to engage the muscles that don’t move much at a desk, like lunges, jumping jacks, or even dance breaks, are totally viable options.
The Key Ingredient: Protein
As Thompson suggests, let’s put the spotlight on protein here.
How much protein should one eat? General recommendations are 0.8 g per kg of body weight (a kg equals 2.2 pounds, so a 220-pound person would need 80 g of protein daily by that measure,) but research suggests higher amounts may be better.
One small study split women into two groups, high-protein intake (2.5 g per kg of bodyweight) and low-protein intake (0.9 g per kg of bodyweight), with both groups performing the same 8-week resistance training program. Both groups increased strength at similar rates, but the high-protein group added more than triple the muscle than the low-protein group, with fat mass decreasing in the high-protein group and remaining unchanged in the low-protein group.
A 2024 JAMA study of more than 8000 people over 10 years found higher protein intake was associated with lower mortality rates, particularly in older age (the study also looked at older people with kidney disease — higher protein intake also benefitted them). The type of protein — animal, plant, or both — didn’t matter.
A January 2025 study of middle-age and older people with type 2 diabetes and low fitness markers found that higher protein intake may improve muscle mass, low strength, and physical performance. One group ate 0.8-1 g/kg daily for 12 weeks, the other ate 1.2-1.5 g/kg. The high-protein group showed “significant improvement” in handgrip strength and physical performance, while the lower-protein group saw declines.
The combination of protein intake and even the bare minimum “exercise snacks” can still be helpful to those who sit all day. But what’s important is that it doesn’t take much. In particular, for older adults with more sedentary lives than the 20-somethings included in Moore’s study, studies have shown that small bits of movement can make even more pronounced differences when it comes to functions such as mobility and heart health. This is probably true for protein synthesis as well, Moore added. That’s a great reason to get out of the chair at any age.