The Lucky Thirteen

In the book The Workout, Gunnar Peterson, has this theory that every workout consists of only "lucky thirteen" main exercises. But then he adds a different tool, position (sitting or standing), reverse, and twist, to it and you'll never do the same workout twice. It's a very interesting concept. Here are the lucky thirteen exercises he thinks are the most important:

Squat
Lunge
Row
Pulldown (Lats)
Shoulder Press
Shoulder Raise
Chest Press
Chest Fly
Bicep Curl
Triceps Extension
Triceps Press down
Crunch
Reverse Crunch

Interesting. I won't go through all of the twists and positions because then I would write the whole book out for you! But you can do the reverse to almost all of these positions. For example, reversing the bicep curl means having your palms face towards you instead of away from you when you begin. Or in the shoulder press, instead of starting off with your palms away from you, face them towards you and then press up. You can do that standing, sitting on a Stability Ball, or adding it to a sit up.

So it allows you to have some creativity, but it gives you a foundation to start with.