I'm 52 in a few days, last time I maxed out my push-ups I did 109 of them, though if you want to count circuit cycles of push-ups I can do way more than that, and like shan2, I have no idea how many sit-ups I can do.
But the important thing to note is that in the 52 year old body, if you've done much in life, everything hurts. All joints, bones, fingers, toes, you name it. There's pain everywhere to one degree or another, and you get used to smelling like camphor and eucalyptus all the time.
When I do push-ups, my right shoulder hurts like hell, and my left shoulder not only hurts like hell, but actually emits sound, much like the sound made by one of those pepper grinders that they fill with peppercorns and put on the table, when it's twisted. And I won't even mention what my back feels like in perfect push-up position.
So I figure either this guy is a masochist's masochist, or he has lived a soft life and hasn't had his fair dose of personal pain yet. But he's gonna get it! Once you hit fifty, you better start easing back on the throttle a little! Last time I got bucked off a horse, I didn't bounce anywhere near as nicely as I once did! I got right back up, but there's still things hurting from that ride, and that was awhile back!
Cheers!
Rick...