Every house has load-bearing walls—the ones that hold up the structure, as opposed to the ones that just divide a room. You can knock out a non-load-bearing wall on a weekend project and nothing happens. But touch a load-bearing wall without a plan, and the whole house has a problem.
When it comes to our bodies, the skeleton is the load-bearing wall—and keeping it in good condition is just as important as making sure those in our houses are sound.
The frame you can’t see
When most people think about “building” their body, they think about the visible parts: body composition (muscle vs. fat), shape (muscle size), performance (not visible, per se, except in its outcome). That’s the equivalent of paint and siding, footprint, and HVAC efficiency. Bone is the frame inside the walls. You can’t see it, and it doesn’t complain the way a sore muscle or cranky joint does when something’s off—so you probably think about it as often as your home’s framing. Which is exactly why it’s easy to ignore… until it isn’t.
Bone mineral density (BMD) erodes gradually and silently over decades—no ache or other warning sign that tells you the frame is thinning until a fracture (or a bone density scan) reveals how much has already been lost. According to the CDC’s most recent national health survey, about 1 in 8 U.S. adults aged 50 and older already has osteoporosis, and low bone mass short of that threshold shows up in over 40% of people—or more than half among women specifically. And that rate roughly doubles between the early 50s and late 60s. (If you’re on the early part of that curve or younger, this is exactly the point when you can still change the trajectory—although there’s never a poor time to start.)
The good news is that the solution to improving BMD isn’t complicated—it can be found at both the gym and the grocery store.
What actually builds the frame
A cluster of 2025 meta-analyses—spanning thousands of participants, including a good amount of data specifically on postmenopausal women—confirms that resistance training is the single most effective intervention available for maintaining BMD as we age. (If you read the perimenopause tip from a few months back, this will sound familiar—resistance training was already at the top of that list, in part because of exactly this connection.)
Combining resistance training with aerobic work outperforms either one alone. And the detail that matters most for anyone already lifting? High-intensity resistance training outperforms moderate intensity specifically for bone density. (One of the meta-analyses behind this found significant hip and spine density gains in the high-intensity groups, while the moderate-intensity groups didn’t reach that bar.)
That last point is worth a quick review, because “intensity” is a word I’ve written about correcting before: it isn’t how a workout makes you feel, but rather a percentage of your maximal load.
“High intensity” isn’t the kind of session that leaves you gasping on the floor—it’s the kind in which you lift weights that are on the heavy end of your overall strength capabilities. “Moderate intensity,” by contrast, means moderate weight. And moderate weight—despite still being effective for other training outcomes—doesn’t load bone hard enough to trigger the thickening response that makes it stronger.
The carpenter still needs materials
This is where the grocery store comes in—and also where my metaphor earns its keep.
Exercise is the carpenter in this context—it’s the stimulus that does the work of telling your body “build here, this needs to be stronger.” But a carpenter without materials doesn’t build anything, no matter how good he is with a hammer. Just like the carpenter, your body needs the raw materials—all the nutritional components (including minerals and protein) that are necessary for bone growth—on hand before it can actually turn that stimulus into a finished product.
Which means this cuts both ways. Heavy training with poor nutrition is a carpenter showing up to a job site with warped lumber and rusty nails. And loading up on a calcium-magnesium or other bone-health supplement stack without the resistance training to go with it is the opposite problem—materials sitting in the driveway with no one there to use them. Bone density doesn’t respond to either one in isolation. It needs the stimulus and the materials, together, before the body has any reason—or any resource—to build.
Putting it into practice
If you’re resistance training regularly, the encouraging news is that you’re already doing the single best thing available for your skeleton. Still, there are two follow-up questions worth asking yourself: First, are you actually training heavy on a regular basis, or have you drifted toward using solely light or moderate weights (<70% 1RM) and higher reps? And second, is your nutrition actually supplying the materials—enough minerals (e.g. calcium, magnesium, zinc) and overall caloric intake—to let your body use that training? If either answer is no, consider where you might make some changes—even a single heavier training session each week and one better daily nutritional choice can make a difference!
If you’re not currently resistance training, start with a session or two per week built around a handful of compound movements, with moderately heavy (for you) weights and longer rest periods. (Check with your doctor first if you have specific health concerns, particularly an existing bone density diagnosis.) You don’t need to walk in lifting heavy on day one—technique and consistency come first, load comes after. But know that the heavier end of your capable range is exactly where the best results will be found.
You’re going to spend more time in your body than your house—it’s only sensible to make sure the framing holds up.