But Lise that is where the mind comes in. My coach once told me, if you tell your mind "I'm going to run 8 miles" it conditions itself to that distance and rarely will you feel like running longer. But you will be able to handle the distance. So if you tell yourself "i'm going to do an IM. It's going to be long, and it's going to be hard, but if I take the race in little chunks I CAN do it" you will be sucessful. It's all up top! You can't let your mind talk you out of it. You just have to know how to mentally break it up. And well, or course, you have to TRAIN. There is just no easy way around that. But if you put your miles in it will take you to the finish line race day.