exerciseJason Gay of the Wall Street Journal has 27 rules for the gym, and then 25 more. Below are some interesting examples of norms and insider know-how.

There's coded language:

"Great job!" is trainer-speak for "It's not polite for me to laugh at you."

Be cautious about any class with the words "sunrise," "hell," or "Moby."

Getting the etiquette of workout machines is important:

Gyms have two types of members: Members who wipe down the machines after using them, and the worst people in the universe.

Understanding interpersonal dynamics is the key to long-term success and acceptance by the in-group:

There's the yoga instructor everyone loves, and the yoga instructor everyone hates. Memorize who they are.

The scale in the locker room weighs everything seven pounds heavier. Do NOT dispute this. The psychological stability of the entire gym membership depends on this.

Gym clothing also sends important signals:

Don't buy $150 sneakers, $100 yoga pants, and $4 water. Muscle shirts are for people with muscles, and rhythm guitarists.

Here's a helpful rule on gym clothing. If you're not sure your shirt smells? Your shirt smells.

The most important lesson is that maybe you don't need a gym after all:

Fancy gyms can be seductive, but once you get past the modern couches and fresh flowers and the water with lemon slices, you're basically paying for a boutique hotel with B.O.

The best gym on earth is outside, and it's totally free.

But if you do choose the gym route be sure to get the politics right, or else!