Repeat after me: taking breaks does not mean you're weak, lazy, or not a good runner. I used to think this, and friends, I was wrong. If you need the break, take the break. Stretch out. Catch your breath. Walk for a minute. Keep it short and sweet, because long breaks can cause your muscles to tighten up and get cold, but don't force yourself to keep going if you know taking a breather will help you out.