[joeyo]

"Two or three redbulls" sounds a bit extreme to me but the principle itself is sound[1]. The idea is that a short nap helps you feel refreshed if you can keep it just that: a short nap. Caffeine also can help you keep alert, but it takes a while to absorb it when taken orally, just the amount of time as a short nap. So when the caffeine wakes you up you are ready to go.

1. With the caveat that 45 minutes sounds too long to me. It should only take 15 minutes or so for the caffeine to get through your digestive tract. Also, sleeping longer than 15-20 minutes probably results in significant grogginess.