If you are over thirty and still this strong, then you have my respect and envy. I’m not even forty and even I would say a >7h economy flight (middle seat particularly) can take about two days to recover from.

How much money would you pay for two extra days of life? In the end, time itself is also “fleeting”, if you want to put it that way. But I sure as heck would fork over the money if I had it.