Fisting, perhaps

What the hell is it with the "fist bump" these days? Is it tantamount to a high-five? Has it supplanted the high-five? Can I do it with girls?

It is less binding than a handshake, but also more personal. I suppose it shares space with the handshake-hug, perhaps filling in where homoerotic undertones are unappreciated, like after a hard mountain bike ride or a game of racketball. (After all, it is well-documented that strenuous exercise and hugging may lead to gay sex.) Golf, on the other hand, needs the handshake-hug. Fist-bumping works for that awesome approach shot you dropped five feet from the pin but falls short of recognizing the awesomeness of the 5-hour walk you just took with your buddy.

Theorem:

The level of inter-personal physical acknowledgement is inversely proportional to the energy concentration of the acknowledeged activity.