The endurance athlete is the ultimate realist.
Run your own race at an even pace. Consider the course, the temperature, the weather, and most importantly, your current level of fitness.
There's no satisfaction without a struggle first.
Road racing is rock 'n roll; track is Carnegie Hall.
Overtraining is the biggest problem incurred by runners who lack the experience or discipline to cope with their own enthusiasm.
During long, slow distance training, you should think of yourself as a thoroughbred disguised as a plow horse. No need to give yourself away by running fast.