Well, I'm 53 and I am called Silver for a reason (hair). And I haven't noticed anything. Granted in my group I am the one expected to do the heavy lifting and the group averages about 34.
I do have some thoughts on the subject however. think about what these kids (and you and I) see every day; so many people, even in their 40's who cannot get out of their own way. And from what I can tell that is the majority of older folks. People live by patterns, if you constantly see 50 somethings that cannot walk a flight of stairs without getting winded you begin to expect any 50 something to be that way. Was talking to a friend last night, she told me that her dad was my age and couldn't do half of what I do, paused and said, if he had been dancing with me like you have he'd be dead now.
Pointing and Laughing, haven't noticed it, now generally I hang out with friends and they are all much younger than myself so that may be a factor. However this year I spent a lot of time with a 45 year old woman and we did all the normal silly stuff and again I didn't notice any pointing and laughing. I will admit that we both look younger than we are and are both in pretty good shape (she has a great shape) but neither of us will pass for 30.
I like playing with fire.