Crankin, two things; one start taking the D3 two, start taking calcium after the rides. Ever notice there's no calcium in sports drinks?
I've even talked to the NUUN company about this. they said only cyclists lose calcium , not the other kinds of athletes that use their product, so they're not going to add calcium. So after any ride that i sweat during, I take extra calcium. that plus taking a lot more D3 than "normal daily requirements". I'll let you know in 2 years (sigh) if it's helping.
ps, i've read some stuff about Fosomax and i'm not really sure the kind of bone it builds is going to make us any better off.