In my second clipless fall the other day I gently fell on my hip. I have bruises on both shins but my hip is fine. As I contemplated that on the remainder of the ride, I began wondering if I ought to schedule an appointment for a bone density test. My mom has osteoporosis, and she has had broken bones from just simple falls. I've never broken a bone but heredity is a risk factor.
Has anyone else considered this? We've discussed knees, hips, backs, hearts, colons, eyes, and other 50+ parts, but I don't recall seeing the topic of getting our bones checked. It would be nice to know that my hips or other parts won't shatter into a million pieces if (when) I fall off the bike (again).
Bone density tests (and bone density) have almost no correlation with bone breakage. It's a feel-good exercise that's a money earner for the medical industry. Bone quality is as or more important than density. That's the quality of the microarchetectural structure of the bone and it's not measured by a bone density test.
Tests on mountain bikers indicates far better bone density than road bikers. Since road biking is a non-weight bearing activity, it's probably as bad as swimming for bone health. I would add jogging and/or weight training to your weekly activities. Jogging not only is weight bearing, but the impact/shock generates electrical impulses which also helps build bone strength.
The problem with weight training is that there is little scientific research relating weight training and health issues like bone breakage. What there is I found in Physical Activity and Health
(an $80.00 college level text book that's relatively current (2006) and very readable) and Younger Next Year . Though the latter should be read by everyone, it doe not deal significantly with bone strength.
In Physical Activity and Health it's reported that the only evidence of bone strength improvement is when you lift relatively heavy weights (something like at least 10% of bone breakage) to failure. An example might be about 8 reps of a weight that is 85% of a weight that you can only lift once for that particular exercise. You need multiple exercises, 3 circuits and at least twice a week. The best definition of failure I've found is that rep where you can't maintain good form/technique: you don't want to hurt yourself. In that vain, I wouldn't want to see what my 1 rep max weight was without professional help.
I lift to failure in 6 to 8 reps for about 6 or 7 exercises. You want total body exercises as opposed to isolating muscle groups. Squats is one of the best and helps a lot on the tough climbs. Upright rows and push-ups are also great, but you'll do more reps to failure on the push-ups.
I'm 69 and don't worry a lot about falling on my mountain bike. I fall several times a year and I ride some fast/rough downhills. But, I've been weight training for about 30 years and jogging for over 40. Plus I've done a lot portaging of over 100 lbs and lots of backpacking, so I don't worry about it. It all helps slow the after 40 decay process.
From population studies, it's apparent that those countries with the highest dairy intake have the highest bone breakage. High doses of calcium supplement, media articles and MDs aside, is not the answer.
Also, if your worried about being clipped-in, consider switching to SPD pedals with #56 cleat. It's multi-release and lets go in those falling moments with one's natural knee-jerk reaction. It holds well enough to pedal full-circles and do bunny-hops. I'm a cleat wimp and have never failed to unclip when falling in the 7 years I've been biking. I keep them resonably tight too.
Al