This is not a forum for this sort of thing, so I'm going to make this very brief. It's not clear whether cycling causes low bone density or people with low bone density are attracted to cycling.
In any event, there's a quick answer to your legitimate conern. Have your bone density checked. It's quick and painless.
George Hollenberg MD
> Since joining this list I've read lots about the machines we
\r?\n> ride but little about the human engine that moves the pedals. I
\r?\n> don't know if this subject is off topic, but I recommend it as
\r?\n> an article worth reading for those of us on the list--and our
\r?\n> friends--who spend lots of time in the saddle. I do not know the
\r?\n> demographics of this list, but I would venture a
\r?\n> guess that most of us are not spring chickens, and therefore
\r?\n> issues of
\r?\n> bone density and osteoporosis are very real.
\r?\n> Note the recommendation to ingest calcium during long, hot
\r?\n> rides, plus the need to cross train. I can say from my
\r?\n> experience venturing into triathlons the last few years that
\r?\n> adding running to cycling -- plus a real commitment to winter
\r?\n> weight training-- has made this 47 year old feel fitter than
\r?\n> ever off the bike and on.
\r?\n> Robert Aguirre
\r?\n> Windsor, ON