If you race hard, it's going to hurt. It's going to be tough.

Runners relish the toughness. Often when we race, more than hitting a time or achieving a place, we most want to prove that we can overcome difficulty and pain. We want to demonstrate that we're made of the right stuff, we have true grit, we die hard - we are, indeed, tough.

True toughness comes from overcoming personal limits. It's fighting against the internal dialogue in your head that stems from your body wanting to slow you down. It's overcoming the feedback signals from your muscles that say they're flooding with acid, or that your fuel stores are running dangerously low. How each runner experiences these sensations of fatigue is completely individual. No one else knows exactly what you're feeling and at what point you might give in to the pain. Toughness is knowing when you've gone past previous barriers and tangled just an instant longer with your brain as it tries to shut you down.