So you've trained for the Philadelphia Marathon or Half Marathon, doing your long runs, tempo runs, speed workouts, everything on your schedule. You are fired up and ready to go on the morning of Sunday, Nov. 22.

But is your mental game in line? It should be because your brain is one major factor that can either hamper your performance or push you forward.

"Research is showing that's what limits us," said Matt Fitzgerald, author of How Bad Do You Want It? Mastering the Psychology of Mind Over Muscle. "If you're running a marathon and you hit the wall, it's not because you've encountered your absolute physical limit."

That might not sound right to anyone who's hit that wall, but research is backing him up.

Fitzgerald has written more than 20 books, most related to endurance . He's long been interested in the psychological aspect of competition, but didn't decide to write How Bad Do You Want It? until science caught up and proved that the brain can affect the outcome.

In the book, not only does he sort through studies that show that the mind can push you over matter, but he also looks at more than a dozen races to see how elite athletes overcame obstacles like inadequate training to win events like the Chicago Marathon and the Ironman World Championship.

Some of the mental exercises in the book require practice and preparation, but Fitzgerald says that if you're running a race soon - say the Philadelphia Marathon or half marathon - there are easy things you can do to help you mentally prepare and gut through the race.

The first is called "bracing." "It's a good idea to expect every race to be your hardest one yet," he said. "By expecting less perceived effort, you're able to tolerate less. In the grinding affair that so many races are, you're mentally unprepared." So if you go into the marathon or half marathon on Nov. 22 and tell yourself it's going to be an easy event, you're not going to be prepared for what will most likely be a trying physical experience. By knowing you're going to run hard, you're more likely to do so and run better.

Another tactic comes during the race, especially if you've gotten down on yourself in tough spots before. "The specific things that you think while you're running a race can either enhance or limit your performance," Fitzgerald said. So if you're struggling and you tell yourself you're struggling and that this is just going to be like the last time you messed up in a race, you're more likely to do so.

"A resting negative thought is very natural when you start to suffer in a race and think negative thoughts," he said. "Being aware of that gives you the opportunity to catch those thoughts as soon as they form and replace them with more helpful thoughts."

Suggestions: "I've been here before and can do this." Or "just relax."

My personal favorite is "Just keep swimming," yes from Finding Nemo. But it works. I got to my marathon personal record that way. And maybe you will too.

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