I don't like to eat too much before I ride, and I just CAN'T eat hardly anything on my early commutes in. It's enough to ask my body to leave by 6:30 for the 1.5hr ride, thinking about digesting food, coffee, whatever that early makes me almost want to hurl.

My ride home is a totally different beast. I get more energy as the day goes on and by 5:00, I'm ready more than ever to ride. I usually am able to eat a couple hours earlier and I always feel great riding home.

It could have been a combination of things for you, in addition to it being your longest ride. I suspect it'll all become easier as you keep it up. I'm hoping that one day I'll jump out of bed, totally awake and feeling alive! Ha!