Pace training: Think fast

[Source: East Coast Cycos newsletter, in Tri-Rudy newsletter, November 12, 2008]

Yes, you need to train your legs, but it's really your brain that dictates your pace.
By Matt Fitzgerald

If you're like most runners, you discovered the importance of pacing the hard way. You started too fast in your very first run or race, and ended up staggering and wheezing through the second half. But you learned your lesson and held back on your next attempt, allowing you to make it to the finish without the urge to vomit. Eventually, however, you may face a new dilemma: You become so good at running conservatively that you finish feeling too comfortable.

Perfecting your pacing--trying to run a certain distance in the shortest amount of time possible without falling apart--is a tricky art. That's because even when we watch the clock, we run largely by feel: We decide whether to speed up, slow down, or hold steady based on how much discomfort we think we can handle.

Until recently, exercise science gave little attention to this mental side of pacing. If you petered out midway through a run, most experts would say your body temperature got too high or there was too much lactate (a fatigue-producing chemical) circulating in your blood. But Ross Tucker, Ph.D., an exercise physiologist at the University of Cape Town, South Africa, and a growing group of exercise scientists believe there is a more complex system at work. Their research shows that your brain reads what's going on in your organs, tissues, and cells while you're running, and then uses that information to get into the right rhythm at the start of a run and then fine-tune your pace as you go. Learning how these internal sensors work is the key to becoming a better pacer and stronger runner.


The Science of Pacing

Exercise scientists were turned on to the idea that your brain controls pace by a German researcher. In 1996, H.V. Ulmer theorized that when you perform a task, your brain focuses on the endpoint (a finish line; when the treadmill clock hits 30 minutes), and it works backward from there, calculating how hard you can push yourself and still complete your workout. Several years ago, Tucker and his colleagues, including renowned exercise physiologist Timothy Noakes, Ph.D., started conducting experiments on Ulmer's theory, which they now call "anticipatory regulation," meaning your brain anticipates when you're going to be done running and regulates your pace accordingly. "The brain controls exercise performance to protect the body from reaching a failure point or a potentially harmful level," Tucker says.

How does your brain know this limit? "The brain receives signals from the body and interprets these signals in the context of the exercise bout," Tucker says. So your brain reads the exercise intensity and checks in with all the various systems in your body (Do you have enough fuel? Are you well-hydrated? What's your body temperature?) to determine if you can keep up that pace and still finish. "Then the brain changes the degree of muscle activation to slow the athlete down or allow him to speed up," Tucker says

In one of Tucker's studies, two groups of cyclists completed time trials in hot and cold temperatures. It wasn't surprising that those exercising in the heat had slower times. However, those in the hot group dropped their pace without realizing it within five minutes of starting--well before their core body temperature rose to a high level. "The fact that they slowed down so early suggests that the pacing decision is made by the brain well before any physiological factor forces the athlete to reduce his speed," says Craig Kain, Ph.D., a sports psychologist and lecturer in the department of kinesiology at California State University in Long Beach. "So you're not slowing down because you're hot; you're slowing down in anticipation of becoming hot."

Although the anticipatory regulation process is designed to prevent you from hurting yourself, sometimes the brain can be overprotective and slow you down before it's necessary. How can you prevent your brain from hitting the brakes prematurely? "We've done research on this, and it seems like the best way your brain learns is from experience," says Carl Foster, Ph.D., professor of exercise and sport science at the University of Wisconsin - La Crosse. "The more you experience fatigue, the more your brain becomes tuned in to your true limits. Mimicking a race experience--by running race pace--at least three or four times during your training will make your brain become familiar with what your body can handle."

Kain offers another strategy: negative-split training. "Running the second half of your workouts faster than the first half will train you to override your mind when it tries to slow you down during the second half of a run," he says.

These training techniques will help both your body and mind get used to the effort needed to do any workout or race at your perfect pace.

For more information on pacing and for sample race-pace workouts, see runnersworld.com/pacing.

Feel Better

Feelings of fatigue are often just in your head. Your body usually has the reserves to push on. Tell that to yourself when your mind tries to slow you down.

Think It Through

You can train to run a certain pace, but it also takes brainpower. Sports psychologist and lecturer Craig Kain, Ph.D., recommends breaking up the distance.

Tell Yourself: "Hold Back!"

"During the first part [first mile of a 5-K, first two of a 10-K, etc.], restrain yourself to counter the adrenaline that could pull you out too fast," Kain says.

Stay Focused

"During the middle miles, you need to concentrate," says Kain. "Your mind will try to slow you down because it thinks you should conserve energy. Being aware of this helps you fight that urge."

Follow Through

"If you've trained properly, you won't need to slow down until after the finish," says Kain. "And if you've kept a steady pace, you won't have the energy to drastically speed up--except for a kick across the finish line." Also, dismiss spectators who shout "you're almost there" when you're not. "If you hear that at mile 20 of a marathon, block that thought. Otherwise, your brain could tell you to pick up the pace--a recipe for bonking--or slow down and walk."


More half-marathon records have been set with even-paced efforts. But marathon records fall with negative splits.