Surprising how body is aging. No, I didn't find any wrinkles yet but I do have few gray hair. It's a little scary to find out that your back aches from time to time, that you're no longer as flexible as few years earlier. For me, crossing the borders between youth and adulthood is more dramatic than change from a kid into a teen.
To revive my not old yet-no more young bones and muscles, I like to stretch. Slowly, to feel how body is adjusting, how blood is circulating faster and easier, how the level of my energy is rising.