Startups feel like sprints in the beginning, but for any of us who have done this before, we've learned that it's a marathon.

We're judged by our speed when we start — and our endurance when, and if, we finish.

When Does "Pacing" Ourselves Start to Matter?

Not in the beginning. In the beginning, it's full sprint all the time — or at least that's the way it feels. We've got a headful of energy and we're ready to tackle every problem with longer nights and more stress.

But it doesn't take more than a year or two before those late nights and sustained stress start to run us down. Getting fired up over every last problem, and the stress that comes with it, begins to burn our cortisol levels to a dangerously low point.

At that point, the spr...