One of the most common pieces of advice that I hear newbie runners tell each other is to “zone out” while on a run. Be it through music or simply letting go of your thoughts, as long as you’re not thinking about the fact that you're running, they say, then you’re better off.

That’s bad advice. Our brain uses two operating systems to manage running—the ancient, subconscious part (a.k.a. the reflex brain, located in the brain stem), and our much smaller, conscious section (the prefrontal cortex, housed in the frontal lobe). When we run zoned out, the reflex brain takes over, and stress builds from exertion, heat, even starting too fast. That stress can trigger a surge in cortisol, which lowers motivation to keep going. The higher the stress, the more miserable you’re likely to feel.

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The point isn’t to obsessively focus on running. Simply thinking of fire-up phrases or keeping a specific game plan in mind (and a realistic pace, of course) can trigger the prefrontal cortex to take over, and temper the flow of cortisol. This way, you control your motivation, even if you encounter stress.

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I personally make sure I have a few words ready to roll—phrases that remind me of proper form or times I overcame common running challenges (like a slow pace or a lack of confidence). Check out my go-tos, at right, for sticky situations.

Knowing how to properly run up and down a hill can improve your running form, strengthen your muscles, and reduce your risk of injury:

preview for How to Conquer a Hill

On a Steep Hill
Rather than burying my head into my chest and grumbling about my quads being destroyed, I repeat “I love hills!” out loud. It turns on that conscious brain control—so I have more motivation to reach the top—and gets a few grim smiles from fellow runners.

On a Downhill
When flying down a decline, I think ”smooth and light” to focus on staying low to the ground and light on my feet. It helps keep me from pounding down the hill, stressing my hamstrings and shins, or overusing my quads.

To Pick Up the Pace
I literally tell myself, “I’m getting faster,” even if that’s not true. (I won’t look at my watch, either, in case I need the mental trickery.) I’ll also try “I am strong” as a reminder that I have more left in my tank before the finish line.