I have been having a blast since discovering climbing six years ago. I’m 58, female, about 5’3”, 113 pounds and Caucasian. I recently had a bone-density study and found that while the Z-score of my arm is 0.00, my lumbar spine and hip are osteopenic at -1.9 and -1.7 respectively, and my femoral head is -2.5: officially osteoporotic. Is my arm-bone density normal because of my climbing? Can I increase the density of my femoral head? What exercises will give me the most benefit to maintain or increase the density of my bones? Am I at a huge risk of breaking my hip? I’m about five years post menopause and haven’t done hormonal-replacement therapy (too much family history of strokes). I don’t exercise daily but skate ski three to four days a week in the winter, sport climb three to four days a week in the summer, and do several backpack trips in the summer.
— Bonehead, Rock and Ice Forum
For those who do not read statistics books for the fun of learning, the T-score is how you compare to a 30-year-old, matched for age, sex and ethnicity.
Measured by how many standard deviations you are from the mean, or middle, of the population, the more negative the T-score, the more likely you are
to fracture with low force. A score above -1 is considered normal, between -1 and -2.5 is considered osteopenia (low bone mass), and -2.5 or below
is considered osteoporosis.
Another measure is a Z-score. This is how you compare to someone your own age, sex and ethnicity and is also measured by the number of standard deviations
from the mean. You haven’t mentioned any other medications or risk factor, so I assume this is postmenopausal bone loss.
Forearm bone density is an unreliable indicator of bone loss, so you couldn’t necessarily say that the 0.0 Z-score is because your arm bones have been
afforded protection by virtue of climbing. That said, any load across a bone has the potential to cause bone deposition, and climbers obviously put
extraordinary load through the upper limb, but it’s a moot point since we don’t have any earlier bone-density studies to compare.
When you fall, either in a harness or when bouldering, your hips move into flexion, which in turn causes lumbar flexion. Add even a slight amount of rotation
and you have a Molotov cocktail of biomechanical forces that can easily lead to a vertebral crush fracture in a susceptible bone. With regard to the
femoral head, the mechanics leading to fracture are wider and more varied, and the bone is even more vulnerable.
I would rather play golf with a ping-pong bat than take up toproping as an end in itself. But the fact is you are at a very much heightened fracture risk,
specifically for your femoral head. At age 65 and up, hip fractures are a sentinel event in the spectrum of your health and have a one-year mortality
Now that your friends know you have frail bones, the general stress around spotting you will cause each of them to succumb to nervous breakdowns. You will
become a loner and start reading What Coffin magazine. Choose a different future and delete bouldering from the fun radar.
If you want to do recreational miles with little chance of falling ,climbing will likely help your bone density and you’ll have a jolly good time. Get
out there and enjoy yourself. There are many exercises you can do, not so much to improve your bone density, but significantly reduce its loss. See
an exercise physiologist and get a specific program.
Along with taking vitamin D and calcium, targeted exercise will improve your Z score because it’s relative to a population that is progressively worsening.
Improving your T-score is much harder and very limited, and usually requires pharmaceuticals.
This article was published in Rock and Ice 222 (November 2014).