Weight-bearing exercises, weight-bearing exercises"¦ I kept hearing that phrase, from my bone nurse, my oncologist, and “osteo-pros"””those of you who’ve been at this bone health thing a lot longer than I have. But I didn’t really know what a weight-bearing exercise is. Lifting weights sounded logical. But surely there’s more to it than lifting weights"¦?
Indeed. And I actually became more confused before I finally figured it all out. For any of you experiencing a similar state of mental fog, here’s what I’ve learned abut weight-bearing exercises, courtesy of this site, and the National Osteoporosis Foundation (NOF).
First, a definition from the NOF. Weight-bearing exercises come in two flavors: "activities that make you move against gravity while staying upright." And "activities where you move your body, a weight, or some other resistance against gravity." I’ve also heard this: "activities where your bones support your body weight."
How do weight-bearing exercises build and maintain bone density? Bones get stronger and denser when they work. And for bones, work = "handling impact; the weight of your body; or more resistance."
OK, I think I understand the theory. So how, specifically, should I be exercising?
Here’s what Dr. Neil Gonter, the health professional right here on HealthCentral’s osteoporosis site, has to say:
"Exercise programs should be weight-bearing. This includes brisk walking, jogging, hiking, dancing, aerobics, stair climbing, elliptical, and numerous team sports such as soccer, baseball and basketball. They should be done at least 4 times per week, for 30 minutes."
Sigh. Easy to say"¦ hard to accomplish. Jogging, with my aching joints (courtesy of a daily anti-cancer drug), is problematic. We all climb stairs"¦ but 30 minutes a day? Dancing (never have, never will); hiking (maybe occasionally); aerobics (all that bouncing around"¦. ouch) And as for soccer, basketball, and baseball"”when? Where? How? Plus, isn’t all of that fast-paced activity kind of dangerous for those of us worried about fractures?
So that leaves brisk walking, and elliptical. I wonder what classifies as "brisk?" Dr. Gonter quotes a study indicating that walking didn’t show "any improvement of bone density at the spine, and that it showed positive, although inconsistent results at one of the areas of the hip (femoral neck region)." Spotty benefit, at best.
And then there’s elliptical. Ah-HA! I can do that. In fact, I step onto an elliptical machine at the gym probably 5 mornings per week, for just over 30 minutes each time. Great! But surely there’re other weight-bearing exercise choices out there; that elliptical gets pretty boring, despite the trashy novels I allow myself to read ONLY while exercising.
So, let’s hear more from the National Osteoporosis Foundation. Turns out there are three kinds of weight-bearing exercises:
"¢High impact: jogging, stair climbing, tennis, dancing, hiking"¦ These are deemed best for building bones in people who aren’t experiencing low bone mass or osteoporosis. Well, that helps. Other physical issues make it painful for me to pursue these anyway; I’m glad they’re not recommended.
"¢Low-impact: elliptical, low-impact aerobics, stair-step machine, walking. Would that be brisk walking? Any walking? I’m still a bit confused, although Dr. Gonter noted that while walking didn’t seem to increase bone mass in the quoted study, the subjects involved didn’t show any decrease in bone mass. So perhaps it’s useful after all.
"¢Resistance and strengthening exercises: lifting weights, elastic exercise bands, pushups/pull-ups, and functional movements (e.g., rising on your toes).
The NOF recommends strengthening exercises 2 to 3 times a week, and 30 minutes of weight-bearing exercises "most days of the week." So how am I doing with this weight-bearing exercise thing?
"¢Elliptical 4x or 5x/week: check;
"¢Weight-lifting twice a week: check;
"¢Brisk 3-mile walk 2x/week: check.
I guess I’m on track"¦. so far. But I still want to know more (how about Pilates and yoga?). And I’m still a bit confused (how come bike-riding feels so strenuous, yet it doesn’t build bone density?) More next time, as I continue to nail down the specifics of one of the best things we can all do for our bones: exercise.