Originally Posted by
tjspiel
Make sure you're eating right and getting enough sleep. Riding more will help. You might just have to slow down going up the the hills and take it a little easier.
Make sure your tires are properly inflated, that your brakes aren't rubbing, etc.
How should my diet be to meet my needs of bicycling regularly?
The brakes aren't rubbing, but I use dynamo powered front and back lights. The dynamo causes significant friction while rubbing against wheel. It could be that this is what caused my relatively much greater exhaustion on the way back. It was night and I had to turn on the lights. Could it be that the old dynamo needs to be oiled or something in order to run more smoothly? And are there any other bicycle light systems that do not rely on a dynamo?