For Lyle Alzado, check Bennet Omalu's work on CTE. Personally, I see no plausible mechanism for exogenous steroids to cause disease, because I see no plausible endogenous mechanism, with the caveat that the stuff we inject is the same we naturally produce. On the other hand the whole idea of supplements is probably made more significant by a high-carb diet which otherwise disrupts normal physiology. So, go low-carb, run a super marathon, finish first, break records, etc.