[James42]

I agree with 3up but at your age it you will definitely want to get some blood tests done befoe you cycle to see where your levels are at. Its very possible that your test is already low and you could be a candidate for trt.
Do lots of research before you do anything. Learn about diet, training and then gear.
Btw. Just because you have been training for 20 years dosnt mean your doing it right.