Originally Posted by
Carbonfiberboy
Back in November I did some sweat loss calculations and concluded that bone loss during cycling
wasn't because of losing calcium in sweat. Turns out I was wrong about that in this post:
https://www.bikeforums.net/21204976-post47.html
and I take it back. Bone loss is due to sweating. It has little or nothing to do with cycling being non-weight bearing, it's just the sweating. There's a good paper on it here:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3145631/
The good news in that paper and other similar studies is that taking calcium about 2 hours before riding attenuates the bone loss. One study used 1000mg calcium citrate and 1000mg of vitamin D3.
There's also a paper showing that supplementing 1000mg/day calcium also increases cycling performance:
https://pdfs.semanticscholar.org/9d3...2565818304.pdf
It's recommended that if one supplements with calcium to also take magnesium in a 2:1 ratio, but not at the same time, though that wasn't done in these studies.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4717874/
i think you need to be careful about making the claim that calcium supplements counter bone loss. in the first link even in their argument for the research they admit that this is only a hypothesis. This same article states in their results that calcium supplementation prior to, or during, does not improve cycling performance, in contrast to the claim in the second link you pointed out. i read only the first link. i can read it in a half hour but i think it would take a couple to fully understand it all, much goes over my head (dammit jim, i'm an engineer, not a doctor). the second llink i began to read but at over 300 pages i quickly gave up.
i suspect that the researchers are on to something though. maybe if i remember, i'll take a tums before every ride.