Weight lifting and kidney damage

[Marvin8]

If creatinine goes up and down with muscle mass, does it make sense to stop lifting or actually TRY to lose muscle mass? Does creatinine, a byproduct of muscle breakdown, damage the kidney's nephrons? If such is the case, why aren't doctors telling folks to avoid all weight lifting? Quite the conundrum.

[Hidden]

creatinine is used as a marker of kidney function due to it’s normally constant and steady excretion from the body via the kidneys. If you have higher blood creatinine it’s usually due to the kidneys being unable to filter as well, or in some cases higher muscle mass, eating lots of red meat prior to test or exercising excessively just before blood is taken. My understanding is that creatinine isn’t damaging it’s just an indicator of how well the kidneys are working.

[Marvin8 in reply to Hidden]

If that's the case, PHEW!!!! On a different note, last time I did my labs, my creatine kinase (ck) went nuts and the doc was concerned. I had exercised strenuously for the first time in a few weeks the day before the labs and didn't tell the doc. Doc told me to stop my statin for a week, stop exercising, then retake my labs. Everything went back to normal. Needlessly worried for one week solid.

[Hidden in reply to Marvin8]

Worrying isn’t it! I’ve read a few publications where they have done studies on people’s lab values after exercise and there seem to be quite a few that are affected. Also factor in on very few occasions there can be lab discrepancies also the technique in which the blood was taken. Prolonged tourniquet and fist clenching have been known to affect some too. So always best to have a repeat.

[Marvin8 in reply to Hidden]

Indeed!