Endurance
The primary question that you need to ask yourself if how you were "spent." Were you winded? Did your legs give out? Maybe both? Your answer will dictate the type of training you will want to focus on. As most people suggested your friend probably has a higher lactate level that he is able to work at. In addition, he has a larger aerobic base due to cycling for a longer period of time. If this is the case you will need to work on both.