Originally posted by ALBOB
Yep, but I don't know what it is.

Seriously, there are a number of reasons people get sick during a workout but it's mostly due to the intense physical stress of the workout itself. If you've seen stars, spoken in tongues, etc you're getting close. The thing to remember is that you don't have to go that far. Getting everthing out of a work out and/or a particular set is very important but you don't have to get sick for it to be effective. Most of the guys you hear bragging about puking after a set are just that, braggards.
No, that's AFTER the workout.