If you have been lifting heavy weights for a while, then you will not think this is a big deal. You would be correct, except that many people over the age of fifty would not think they can do this. The fact is that with consistency, patience and discipline anyone at any age can do this. Heavy weight lifting is also very relative, because it is subject to your body weight. A 100 pound female lifting thirty pounds is working much harder than a 200 pound male lifting thirty pounds.
My clients work at a level subject to their health history, strength training experience and their personal drive.
The basic idea is to learn proper technique and execution before pushing yourself to the limit. Keep in mind however, that it is by pushing yourself to the limit that you will achieve your greatest results.