We're all aware of the benefits of weightlifting on health (strength, fat loss, joint mobility, etc.) One of the benefits I often mention when I tell people I started lifting weights in my late 30s is the possibility that weightlifting may serve as a diagnostic tool for serious medical condtions. If you keep a log book of your performance, I would presume that one may be able to detect that something is wrong (assuming you have ruled out injury, overtraining, the flu or a cold). For example, a prolonged decline in performance in lifts involving many different joints may indicate that one is seriously sick.
Does anyone have any experience or know of anyone who discovered a serious long-term health problem by tracking their performance? Am I overstating the benefits of weightlifting?