Keeping bones strong

It can be hard to care about your bones. You can’t see them (no one ever compliments you on your strong bones!) and you can’t even feel them. Yet bones are the frame on which the rest of your body depends.

And I know the frame image isn’t right. We don’t have a skeleton inside us, as if of made steel. Instead, bones are part of us, living things and like the rest us, they grow and then decay. Sad truth but there it is.

How much of our focus on our heath is misplaced because it’s on outer beauty when inner health and strength matters more?

That reminds me of the line from the 1988 David Cronenberg movie Dead Ringers. One of the twin gynecologists says, “Surely you’ve heard of inner beauty . . . [we ought to have] beauty contests for the inside of bodies.” And maybe if we did, we might care more about our bones.

Bone density matters, especially for women. Many older women suffer from osteoporosis and they may not be doing the kind of exercises that help. Many older women also fear falling and so avoid exercise.  Or they’ve been told that high impact exercise is bad for their joints. But avoiding exercise is a very bad idea. So too is avoiding impact. It’s not even clear that joint health is hurt by exercise. (See Aging and the myth of wearing out your joints.)

I started reading up on bone density and bone strength after a series of stress fractures in my early forties.  They were your standard issue tibial stress fractures, left shin, both times, brought about by running too hard, too far, too soon. Each time I tried to increase my distance past 10 km, I’d get a stress fracture which kept me from moving at all for 6-8 weeks. I’d end the summer with a disabled parking pass, no running, cycling, or walking for me.

You can read about runners and stress fractures here.

On doctor’s orders I nervously reported for bone density testing.  It was the first time in my life I was asked if I still menstruating. Of course I was, I was 42. The question shocked me. But it turns out the doctors have good reasons for asking. Often osteoporosis is first detected when a woman breaks a bone. And early menopause is a significant risk factor.

Excellent news, the scan was great. I have rock star bone density, it turns out. At least I did then.

That is excellent news because you can’t build bones in your forties. Youth is the time to build bones, and from 30 on the best you can aim for is maintaining the bone strength you’ve got.

It’s especially important to start menopause with strong bones.

For women, menopause causes an extreme drop in estrogen, and their greatest bone loss occurs within the first ten years after menopause. That’s why many physicians recommend that women get a bone-density scan when they turn 50 or when they enter menopause, whichever comes first. That first test acts as a baseline. From About Osteoporosis

The more I read about bone health, the more I realized I was an unlikely candidate for early osteoporosis. I didn’t fit the profile. Why not?

First, I didn’t have early menopause.

Second, I’m not thin. This was the first time I’d heard of there being an advantage to being my size and being physically active.   When it comes to osteoporosis, thin women have a greater risk than heavy women.  That’s true even for women who are naturally petite. See Just Being Naturally Thin May Raise Risk Of Osteoporosis In Women (Science Daily). The hypothesis is that the bones aren’t strengthened because they aren’t carrying a sufficient load. I like the idea that just moving about, for me and my bones, counts as a kind of weight training.

Third, if naturally thin women are at increased risk of osteoporosis, the story gets worse if you got thin through calorie restriction. I don’t have a history of severe dieting and eating disorders. Women with eating disorders often lose so much weight their periods stop and they experience the bone loss usually associated with aging. “In terms of bone health, a too-thin woman in her 20s looks a lot like a post-menopausal woman in her 60s. The only real cure is for the young woman to gain enough weight to start menstruating again, and then to maximize her bone density while she can — that is, until about age 30, when bone density reaches its peak.”

Finally, I wasn’t a teenage athlete. In young women athletes, low bone density can be part of what’s known as female athlete triad. Female athlete triad is a combination of three conditions: disordered eating, amenorrhea, and osteoporosis. For more information see here and here. This is especially problematic because (reminder to young women!) you only build bone until about age 30.

Exercise is the best way to keep bones strong.  What are the best kinds of exercises to improve or maintain bone density?

The best exercise for your bones is the weight-bearing kind, which forces you to work against gravity. Some examples of weight-bearing exercises include weight training, walking, hiking, jogging, climbing stairs, tennis, and dancing. Examples of exercises that are not weight-bearing include swimming and bicycling. Although these activities help build and maintain strong muscles and have excellent cardiovascular benefits, they are not the best way to exercise your bones. Exercise for Your Bone Health

Another argument for standing rather than sitting, as if we needed one.

image

Dancing bones

The other reason I was concerned about bone density was because I was reading lots about cycling and bone health. That’s the one risk factor I do have! It turns out that cyclists are at high risk for bone density problems.

Here’s why:

“Your body is continuously renovating your skeleton, absorbing old bone tissue and replacing it with calcium that helps form new bone. Physical activity that includes impact and vibration (running, strength training, even walking) stresses the tissue and triggers the rebuilding process. Cycling, however, has no such effect. Thanks to its seated, off-the-ground riding position, it actually minimizes impact on your skeletal system. And there’s a chance that the more you ride, the greater your risk of losing bone mass, says Aaron Smathers, MS, lead author of the aforementioned study…..

Complicating the issue is yet another by-product of cycling: sweat. You can lose up to 200 milligrams of bone-building calcium in an hour as you soak your jersey on a hot ride. Put in long training miles each week and ride a century now and then, and you’ll deplete your body of so much calcium that it becomes harder and harder to replace, especially as you age. You can counteract this by fueling up on foods with plenty of calcium, but you may need more than just dietary adjustments.” Frame Work: Build Bone Strength

Now, I’m not only a cyclist. I do CrossFit, I play soccer, I run a bit, and I do Aikido and it looks like that’s a good thing. Ironically though I could imagine stopping those other things and continuing to ride a bike into old age. I suspect I’m not alone that in looking for sports without an expiry date and swimming and cycling are both ones that leap to mind.

I joke about a list that I keep of things I’m saving for my senior years. Apologies if you do these things while young. This is just about me. My list includes cruises for vacations and television for entertainment and walking for exercise. I also imagined swimming and cycling (on a good sturdy about town bike) into my 80s. Now it looks like, for bone health, I should keep lifting things too.

See you in the weight room!

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Skeleton on bike

About Sam B

Philosopher, feminist, parent, and cyclist!

2 thoughts on “Keeping bones strong

  1. […] to fall and working to maintain bone strength are important fitness and safety habits for everyone, but especially for women after […]

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  2. […] See Sam’s blog post: Keeping bones strong […]

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