It's amazing how razor sharp William Shatner is at 91. Meanwhile Patrick Stewart seemed to lack all endurance to even sit in a chair at the age of 80. His Comic Con panel this year was kept very short.
Shatner went on for hours, cracking jokes and delivering stories and punchlines while standing on his feet for well over an hour-- he had the vigor of someone still in his prime. Transitioning through subjects, going in depth, moving through questions, all while roistering and being entertaining. Stewart look wheeled out in a wheelchair, like he might make use of a diaper. He had to defer to Alex Kurtzman to answer questions he was asked which was played off as a joke. A little disappointing and takes a little of the hype down for Season 3.
The difference is an appalling reminder of this thing called genetics. That, or Shatner's doing some stemcell treatments.