Quite a lot, actually. But before we talk about muscle, think about this: What do you want to still be doing ten or twenty years from now?
Maybe you want to travel without wondering whether you can handle all the walking. Maybe you want to keep playing golf, skiing, gardening, riding your bike or getting down on the floor with the grandchildren and, importantly, getting back up. Maybe you haven’t thought about it at all. Most of us haven’t. We tend to think about aging in years: I want to live to 80. I want to make it to 90. But what do you want to be able to do when you get there?
That’s where muscle enters the conversation.
For much of our lives, we’re encouraged to think about muscle primarily by how it looks: defined arms, strong legs, a certain body shape. Once we start talking about living well for a long time, though, muscle becomes much more interesting. It helps us get out of a chair, climb stairs, carry groceries, lift a suitcase into an overhead bin and catch ourselves when we lose our balance. It also plays a role in metabolism and how our bodies handle glucose (Wolfe, 2006).
In other words, muscle has a lot to do with whether we can keep doing our own lives.
The Things We Barely Notice—Until We Do
Try something the next time you’re sitting in a chair: stand up without using your hands.
It probably doesn’t seem particularly impressive. That’s exactly the point. Getting out of a chair, climbing stairs or carrying a laundry basket are things we barely notice while they’re easy. When strength begins to change, we often adapt without realizing we’re doing it. We use the railing more. Push off the chair with our hands. Make two trips with the groceries instead of one. Ask someone else to lift the suitcase.
None of those things alone signals a problem. They simply help us see what strength gives us: options.
We naturally tend to lose some muscle mass, strength and power as we age, although how much and how quickly varies. Activity, nutrition, illness and injury all play a role. When muscle loss becomes significant enough to affect physical function, it can contribute to sarcopenia, an age-associated condition that can make mobility and independence more difficult (Cruz-Jentoft et al., 2019).
You don’t need to memorize that word. What matters more is knowing that muscle remains responsive to what we do with it. Adults can continue to improve strength later in life, which means we don’t have to wait until getting out of a chair becomes difficult before we start paying attention. Resistance exercise is an effective strategy for improving muscle strength and physical function in older adults (Fragala et al., 2019).
And if you haven’t done much strength training before? You haven’t necessarily missed your chance.
Think of Muscle Like Money in the Bank
Most of us understand why we build financial reserves before we need them. Waiting until retirement to start saving would be a fairly unfortunate strategy.
There is a useful parallel with muscle. An illness, surgery, injury or prolonged period of inactivity can take strength and conditioning away from us. Starting with greater strength doesn’t guarantee an easier recovery, but it can give the body more capacity to work with. That’s part of what we mean when we talk about physical reserve.
The interesting thing is that you don’t have to wait for something to go wrong to spend it. You use that reserve every day. It’s there when you’re hauling luggage through an airport, walking all afternoon on vacation, moving furniture, tending a garden or carrying something heavy up the stairs.
This is where the longevity conversation becomes very practical. We can talk about biomarkers and biological age, but eventually we have to ask a much simpler question: If I get more years, what do I want to be able to do with them?
If You Walk, Keep Walking. Then Consider Adding Something.
Walking is excellent movement. It supports cardiovascular health and overall fitness, and for many people it is one of the easiest forms of activity to make part of everyday life. Current physical activity guidance recommends both aerobic activity and muscle-strengthening activity because they provide complementary health benefits (U.S. Department of Health and Human Services [HHS], 2018).
But walking and resistance training don’t ask exactly the same thing of the body. Muscle responds to resistance—to being asked to work against a load. That load can come from dumbbells, machines, resistance bands or your own body weight.
This doesn’t require walking into a gym tomorrow and picking up the heaviest thing you can find. If you’re starting with chair squats and resistance bands, that’s a perfectly legitimate place to begin. Someone who has trained for years will need a different challenge. What matters is starting at an appropriate level and gradually asking the muscles to do more as they adapt. Progressive resistance training can improve strength and physical function across older adulthood (Fragala et al., 2019).
Think of that resistance as a message to the body: We’re still using this. Keep it around.
And Then We Have to Feed It
If we’re going to ask muscle to work, nutrition belongs in the conversation too.
Protein provides amino acids the body uses to maintain and repair tissues, including muscle (National Academies of Sciences, Engineering, and Medicine, 2005). That doesn’t mean everyone needs to start carrying a shaker bottle or calculating the protein content of every almond. It does make it worth looking at an ordinary day of eating and asking whether protein regularly appears on the plate.
Depending on how you eat, that might mean eggs, dairy foods, fish, poultry or meat. It can also mean tofu, tempeh, soy foods, beans, lentils and other plant-based sources. Individual needs vary with age, body size, activity, overall diet and health, and some medical conditions require individualized nutrition guidance.
We can go much deeper into protein another day. For now, the connection is enough: muscle needs to be used, and the body needs enough nutrition to support it.
Now, Back to That First Question
What do you want to still be doing ten or twenty years from now?
Don’t give yourself a fitness answer. Give yourself a life answer.
Maybe you want to take the trip you’ve been putting off. Keep playing tennis. Dance at your child’s wedding. Live independently in your own home. Carry your own groceries. Spend an afternoon walking through Rome and still have enough energy to go out for dinner.
Those answers are the reason muscle belongs in a conversation about aging well.
Yes, maintaining strength can support physical function. Yes, resistance training and adequate nutrition matter. And yes, having greater physical capacity may become especially valuable during a period of illness or recovery. But we don’t have to care about muscle only because we’re afraid of what might happen someday.
There is also everything we want to do today.
Most of us aren’t interested in living longer just so we can collect more birthdays. We want the years because we still have plans for them. Muscle won’t determine all of what those years look like, but it may help us remain physically capable enough to participate in more of them.
So here’s something worth noticing the next time you stand up from a chair, lift your suitcase or climb a flight of stairs: these ordinary movements are using something worth protecting.
That’s what muscle has to do with it.
References
Cruz-Jentoft, A. J., Bahat, G., Bauer, J., Boirie, Y., Bruyère, O., Cederholm, T., Cooper, C., Landi, F., Rolland, Y., Sayer, A. A., Schneider, S. M., Sieber, C. C., Topinkova, E., Vandewoude, M., Visser, M., & Zamboni, M. (2019). Sarcopenia: Revised European consensus on definition and diagnosis. Age and Ageing, 48(1), 16–31.
Fragala, M. S., Cadore, E. L., Dorgo, S., Izquierdo, M., Kraemer, W. J., Peterson, M. D., & Ryan, E. D. (2019). Resistance training for older adults: Position statement from the National Strength and Conditioning Association. Journal of Strength and Conditioning Research, 33(8), 2019–2052.
National Academies of Sciences, Engineering, and Medicine. (2005). Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids. The National Academies Press.
U.S. Department of Health and Human Services. (2018). Physical activity guidelines for Americans (2nd ed.).
Wolfe, R. R. (2006). The underappreciated role of muscle in health and disease. The American Journal of Clinical Nutrition, 84(3), 475–482.
Sources reviewed: August 17, 2026.