THE MAGIC MILE——From the October 2009 issue of Runner's World

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THE MAGIC MILE
How to adapt this time-tested workout to boost your fitness or set a PR.
By Michelle Hamilton

When it comes to effective workouts, mile repeats are a classic and versatile training tool. Popularized back in the late 1970s by athletes such as Alberto Salazar, who ran them before winning his first New York City Marathon, the workout is enticing, in part, because of the distance itself. The mile, after all, lies at the very heart of the sport, as the unit from which all things running are measured—speed, daily distance, races, even lifetime achievement. Plus, by tweaking the pace, the number of repeats, and the duration of the recovery between efforts, runners can adapt mile repeats to any goal—whether it's improving fitness or setting a marathon PR. "You can do mile repeats on the road or a track, and they can be done in a number of ways to accomplish different training goals," says Tony Coffey, head coach of the Impala Racing Team in San Francisco.

From a physiological perspective, the mile is a "middle distance." It's short enough to be run fast (by experienced runners) to build speed. But it's also long enough to build stamina, when performed at tempo pace. "Mile repeats provide excellent all-around conditioning for runners competing in most any distance," says running coach John Kellogg of Ithaca, New York, who has worked with professional and collegiate athletes for 29 years.

Here's how—and when—to use mile repeats to boost endurance, get faster, and practice pacing.


BUILD STAMINA
Runners often develop stamina with tempo, or lactate-threshold, runs (typically 20 to 40 minutes at a "comfortably hard" pace). However, you can break a planned tempo run into mile repeats, with quick recovery, to get the same benefits with less fatigue, a particularly useful strategy for novice racers. More seasoned runners may find they can add volume— that is, turning a planned three-mile tempo run into four mile repeats.

THE WORKOUT: Two to six mile repeats at tempo pace (about half-marathon pace, or 5-K pace plus 30 to 40 seconds) with a 60-second rest between intervals. "The short rest keeps your heart rate up, but you still get the physical and mental break of the rest period," says Coffey. Newer runners may take a two-to three-minute walk break; the goal is to run each mile at close to the same pace.


INCREASE SPEED
To get faster, you have to increase your VO 2 max, or the amount of oxygen your body uses to produce energy, which means running short repeats at a speed faster than 5-K race pace. But for beginners or those new to speedwork, that pace can be impractical. Enter the mile. "You can run mile repeats at 5-K or even 10-K pace and still sufficiently target VO 2 max," says Andrew Kastor, head coach of the High Sierra Striders in Mammoth Lakes, California (and husband of elite marathoner Deena Kastor). "Those speeds are more manageable."
THE WORKOUT: Two to three mile repeats at 5-K to 10-K pace with two to four minutes rest between intervals. If you're aiming for a 5-K or 10-K, do this workout every second or third speed session. Runners training for a half or full marathon should do this workout once every two weeks. If your 5-K pace is slower than an eight-minute mile, run repeat 1-Ks (1000 meters) instead of miles to ensure you can maintain the pace and to avoid undue fatigue, says Kastor.


LEARN RACE PACE
"Doing mile repeats at race pace is critical for new and experienced racers because they really teach you that specific pace," says Susan Paul, an exercise physiologist and running coach with the Track Shack in Orlando. "It mimics the physical and mental challenges of racing." Runners targeting 5-K and 10-K races can match the number of repeats to the race distance (e. g., three repeats for a 5-K) to serve as a dress rehearsal for the actual event.

THE WORKOUT: Two to eight mile repetitions at goal race pace with two to five minutes rest. "Pay attention to the stride, the arm swing, and the breathing rate," says Paul. "This will help your body 'memorize' that speed." When you first try the goal-pace-mile workout, do two to three intervals followed by a three-to five-minute recovery jog. As you get closer to your goal race, add more repeats and decrease the recovery period. To fine-tune your timing, include this workout in the final three weeks of training.


Run Better
Make it harder: Do mile repeats on a slight grade. The uphill mile develops leg strength, the downhill improves leg turnover. Both help you run faster.



How to Time Your Perfect Workout

Mile repeats provide benefits during every stage of your training

THE WORKOUT AND WHEN TO RUN IT

2 to 6 x 1 mile at tempo pace: Early season, or any time to maintain fitness
2 to 3 x 1 mile at 5-K pace: Midway in training; 10 to 14 days before racing
2 to 8 x 1 mile at goal race pace: Three to five weeks before goal race

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It is a pretty valuable tutorial.