for how creatine might help maximal exercise performance
see here:
http://www.healthy.net/asp/template...article&ID=1667
When creatine enters skeletal muscle, it does take water with it, hence the "pump" - but this "pump" has nothing to do with the biochemical mechanism by which increasing free creatine in the cell contributes to the ability to perform maximal exertion.
Here is my understanding of the process.
Essentially, it is thought that free creatine supports the PCr energy system, which is the first source of energy for maximal exertion - e.g. sprints, heavy sets. The PCr energy system is pretty much done w/in the first 5 seconds of exertion. But then when you rest, you replenish PCr for the next set or sprint. It may take 30-60 seconds to replenish PCr (I don't have a reference with me here to be certain).
So, adding creatine might enhance the PCr system which might work to increase strength in these ways:
1) allow you to do 1 or 2 more reps in that heavy set.
2) allow you to recover faster between sets - e.g. reduce rest from 60 sec to 45 sec, or 45 to 30 sec.
3) allow you to exert more force - that is press a heavier weight in the set.
All of these allow you to increase volume and/or intensity of your workout - and that is what is increasing your strength and/or resulting in hypertrophy.