Oh yes, wise use of caffiene (to wake up or stay awake, to finish an essay due the next day, to race...) is a gooood thing.

SuzyBrd... yes caffeine does elevate the HR... but in a race this can be a good thing. Before a TT (time trial) for example, you ride about, warming up your muscles, for as long as you can until the start... but the other thing you are doing as you ride back and forth is you are lifting your heart rate so you can start and get straight into maximum effort.

I TT, and I always have a "V" (similar to Red Bull I guess). In 250ml of liquid it gives me 78mg of caffiene and 28g of sugar. I drink it about 10mins before my start time.... I use that timing because after a morning coffee i feel it hit my system 10-15 minutes after drinking it.

I also take a GU a minute and a half from starting - it will kick in and give me extra punch in my thighs when I am 10-15 minutes from the finish line.