The M and MZone calculations are something you should be using and learning for yourself in sit and go tournaments. The M is more adaptable for multi-tournament play, but in single table sit and go tournaments M has its value as well.

Essentially the M is calculated by dividing your stack by the total of blinds and antes. You don't normally have antes in a sit and go so just combine the blinds and divide them into your stack. The resulting number is your M. If your M is between 1 and 5 you are in the red zone. If it's between 5 and 10, that is the orange zone. The yellow zone would have an M of between 10 and 20, while the best place to be is in the green zone having an M of 20 or more. There is also a grey zone which is less than 1, and when you are there your stack is so low you are virtually out of the tournament.

Let's say you have 1200 chips left and the blinds are 100 and 200. Your M would be 1200 divided by 300 equaling 4. With an M of 4 you are in the dangerous red zone. Let's say across the table your opponent has 3560 chips. His M is 11.9 and he is in the yellow zone - relatively more comfortable than you.

Dan Harrington says the philosophy behind the color zones is that each one will have a bearing on your style of play. If you are traditionally tight, but find yourself in the orange or red zone, you are doomed unless you pick a hand and run with it. You may certainly lose with a hand like 77, but you won't stand much of a chance anyway if your stack dwindles into the red and grey zones.

We all know what happens when you are in the red and grey danger zones. A big stack calls you with trash and beats your AQs with 93os. It can be aggravating, but really, he was right to play you with that hand because you let your stack dwindle too low. It's a mathematical equation as opposed to hand strength.

Download the mzone spreadsheet and have some fun with it in your sit and gos. Very soon, you will know instinctively what zone you are in, and how you'll need to adjust your strategy. What I might suggest is to load up a final table of an MTT and watch the players. While you are watching the tournament input the blinds, antes and each player's stack into the spreadsheet. This way you will get to know the range of zones, watch how players react to them, and be able to make quick calculations in your head.

It is also worthwhile to watch here what hands players play, and from what position given their MZone situation. If you do this while playing sit and go tournaments, and eventually move up to playing multitable tournaments you will have a hand up on your opponents if you can calculate your Mzone at critical stages of the tournament.