Once a week i come home from work, eat tea, let it settle for half an hour then go out for a 15-20m bike ride. For the first 20mins i have virtually no energy, this is because of the diversion of blood to my tummy isn't it? Realistically i couldn't have tea after as i'm famished when i get in and don't want to start downing energy products either.
May as well mention i have very fast metabolism and find energy resources problematic during exercise.