Lessons from the intersection of science and coaching.

and (supposedly) died, the marathon has been viewed largely as a test of

endurance. “If you want to run, run a mile,” legendary Czech distance runner Emil Zatopek (1952 Olympics gold medalist at the 5,000, 10,000, and marathon) once said. “If you want to experience a different life, run a marathon.” But these days, more and more runners are realizing that if you want to run your best marathon, you also need to be fast. If in doubt, consider this: Wilson Kipsang’s 2013 world record (2:03:23) was run at a faster pace than anyone prior to 1950 ever managed to run a 10K … ona track.

Not that endurance is irrelevant. If your body isn’t prepped to go 26.2 miles, it really doesn’t matter how fast you can run a mile repeat. “If you have to choose between intervals or long runs, I’d say long runs are better,” says Tom McGlynn, founder of the online training program runcoach. But that doesn’t mean everything should be centered on the long run. In fact, weekly long runs may be counterproductive, increasing the risk of injury and leaving you too tired for other high-quality workouts, says elite coach and exercise physiologist Owen Anderson. “Implicit in the philosophy of the long run is the suggestion that the human body will somehow forget how to go long . . . unless a weekly battering is administered to the leg muscles,” he writes in his new book, Running Science. “Nothing could be further from the truth!”

If all you’ve ever done is endurance, you may be shocked by how much you can gain by adding a bit of speed to your regimen. A case in point is a woman who started doing my club’s track workouts a decade or so ago. She’d run many marathons but had never broken 3:33. Over the next few months she worked on speed, won a couple of local 5Ks . . . and scorched a 3:14 finish in that year’s Boston—a 19-minute PR. And she’s not the only one to have accomplished such a feat. The bottom line is that if you improve your speed at shorter distances,

= since Pheidippides allegedly ran into Athens, croaked “Victory is ours,”

you have a decent chance of improving it at longer ones, then longer yet, until eventually that improvement carries all the way up to the marathon. It’s something the pros have long known. Before moving up to the marathon, Shalane Flanagan had set three American track records at shorter distances (3,000 meters, indoors; 5,000 meters, indoors; and 10,000 meters, outdoors).

Maxing your VO,max

Physiologically, the quest for speed is built around three variables: VO,max, running economy, and lactate threshold. Each deserves an in-depth look.

VO,max is a measure of the maximum amount of oxygen your body can process at peak effort—basically a gauge of the power of your aerobic engine with all the parts: heart, lungs, capillaries, and muscles—working at aerobic maximum. It’s typically measured on a treadmill test, which many hospital laboratories or sports clinics will do for about $150 to $200. (But shop around; I’ve seen prices as high as $350.)

It’s been long known that there’s a rough correlation between VO,max and racing performance. The average 3:20 marathoner, for example, might have a VO,max of 45 to 50. Ryan Hall in his prime tested at 78. Thus, if you’re the 3:20 marathoner, you might, in theory, be able to close one-sixth of the gap between you and Hall—a whopping 12 1/2 minutes—by adding a mere five points to your VO,max.

But like many things at the intersection between exercise physiology and training, it’s not quite that simple. Yes, you can improve your VO,max. But probably not by as much as you’d like. In a 1978 study in the European Journal of Applied Physiology and Occupational Physiology (Daniels, Yarbrough, and Foster 1978), a team led by Jack Daniels, author of Daniels’ Running Formula (Daniels 2013) found that the average runner can increase it by only 5 percent to 15 percent—depressing news for most of those trying to turn a four-hour marathon into a Boston qualifier.

Also, VO,max is developed through years of training (with possible assists from altitude training, altitude tents, and heat training), and there comes a time at which experienced runners have probably made the bulk of their potential gains. After tracking 33 elite Spanish runners through four years of intense training, for example, a 2005 study in the Journal of Sports Medicine and Physical Fitness led by Alejandro Legaz Arrese of the University of Saragossa, Spain, found the runners’ VO,maxes to be “essentially unchanged” (Legaz Arrese et al. 2005).

“In a nutshell, VO,max reaches a plateau if you train hard,” says John Halliwill, an exercise physiologist at the University of Oregon.

That said, many of us may not have trained hard enough to have hit that plateau. “People in very intense training programs, working daily with a coach,

are probably pushing themselves to the point where they’re probably not going to make changes in VO,max,” Halliwill says. “But others may have reached a temporary plateau, [and] if they did a more aggressive program, they might see additional gains.”

He notes, for example, that part of what happens during VO,max training is that the heart becomes better at pumping large quantities of blood. A sedentary person’s heart, he says, might be able to pump 2 liters of blood per minute. “An elite’s can do 40 liters per minute. That’s a huge transformation. It takes time to go through that sort of adaptation—and also the right [training] stress.” And VO,max development doesn’t involve only the heart. “You also need adaptations in the legs,” Halliwill says. “The blood vessels need more capillaries. The muscles need more mitochondria and enzymes that process food for energy. All of these need to adapt.”

Classically (other than simply years and years of base training), the best way to spur these adaptations is with “long” intervals of three to five minutes, typically done at or near 5K pace. Elites might do these as mile repeats, but for the rest of us, online coach/exercise physiologist Jason Karp suggests two to three miles’ worth of 800s, 1,000s, or 1,200s, on recoveries slightly shorter than the duration of the interval. (I have my runners use slow 400-meter jogs.)

These are exactly the type of workouts that got my 3:33 marathoner her 19-minute PR.

But there’s another piece of the puzzle, and that’s vVO,max.

Running fast

vVO,max is the pace you’re running when your body first hits VO,max. (The extra v means velocity—as in “pace.”) It’s by no means your top speed, but aerobically, you’re maxed out. Book author Anderson puts it at about the pace you can maintain for a six- to 10-minute time trial—for many of us, somewhere between 1,500-meter and 3K race pace. A six-minute all-out time-trial, in fact, is a good way of estimating the proper pace.

In part, training at vVO,max might simply be another way to improve VO,max. But it’s considerably faster than traditional training VO,max training paces—fast enough that it should also tax your body’s running economy: its ability to make the best possible use of the aerobic power that nature and years of training have given it.

Partly, running economy relates to running form. When I have marathoners do fast intervals, part of what I want them to do is to learn to hold their form together, even as they’re tiring—something that’s as important for experienced runners as for beginners. “Personally, as I lose focus and begin to tire, my left hand makes a fist and my arms rise up,” says 2:38 marathoner Amanda Rice.

“Learning to stay in the moment and maintain proper form is crucial to successful racing.”

But there’s also a physiological factor. Halliwill explains it in terms of mitochondria (the cellular power plants that produce aerobic energy) and ATP (the high-energy molecule that muscles use to store that energy). “There are two parts to this,” he says, “how much ATP your mitochondria can generate for a given amount of oxygen, and how much muscle force you can generate from that ATP.” The first of these, he says, may involve biochemical processes that might not be easily changed. But the other—how much forward propulsion you get from any given amount of energy—might be more malleable, he says, perhaps tied to “whether we’re wasting a lot of energy, or doing it in the most economical way.” Veronique Billat, an exercise physiologist at the University of Lille, France, adds that yet another source of running economy might come from improvements in what she calls the legs’ “elastic energy reinstitution”—basically the energy returned you get from stretched muscles as they rebound to launch you from one stride into the next.

Running-economy training, not surprisingly, involves running a good deal faster than marathon pace—whether it’s by intervals on the track or fartleks. Billat advocates very short, fast intervals, on very short recoveries. Over the years, she’s developed several protocols, but her favorite is a (very fast) fartlek. It requires a heart rate monitor, a fairly precise knowledge of your vVO2max (either from a lab test or a six-minute time trial), and a GPS watch or good sense of pace. After warm-up, pick up your pace to vVO2max and hold it for a minute. Then cut back to tempo pace (perhaps 40 seconds/mile slower) until your heart rate drops by about 15 beats per minute. When it does, speed back up to vVO2max but for only 30 seconds this time. Then repeat tempo-pace recoveries and 30-second surges as long as you can (not all that long for most people). This type of workout is totally alien to most marathoners, but Billat believes it is a key to success for all race distances from the 1,500 meters to the marathon.

Billat intervals, sometimes called “30-30s” (because the recovery will probably take about 30 seconds) aren’t the only way to improve running economy. If you want something more traditional, McGlynn suggests short intervals (200 meters to 400 meters) every other week, at somewhere between 1,500-meter race pace and vVO2max: total volume, no more than 8 percent of your weekly total. (I would limit this to 2.5 miles at 1,500-meter race pace, or five miles at vVO,max, no matter how many miles a week you’re running.) For a complete speed program, McGlynn adds traditional VO,max intervals, such as miles, 1,200s, or 1,000s, twice every three weeks, run at 10K pace, with each session at up to 10 percent to 12 percent of total weekly volume. (These are slower than Karp’s VO,max intervals, but the extra volume produces a similar training effect, somewhat more palatably for many marathoners.) Thus, McGlynn says, “a 60-mile-per-week

runner might do 6-7 X 1 mile, or 12 X 1,000m, all at 10K pace.” Chicago-based marathon coach Brendan Cournane also likes traditional VO,max intervals (about four to six minutes) but prefers to make them slightly faster (with fewer of them), gradually cutting the pace down toward 5K pace as the marathon approaches and cutting the recoveries to as little as 45 seconds.

Such training works only if you do something unnatural to many marathoners: run a short race or time trial: six minutes for Billat’s 30-second intervals, a 5K for Cournane’s Chicago Marathon trainers. “I want them to know what their 5K pace is,” Cournane says, adding: “a recent 5K, not four or five years ago.”

Tom Derderian, coach of the Greater Boston Track Club, adds that short races are valuable in and of themselves. One benefit is psychological. If you run a few 5Ks, he says, your marathon will feel more relaxed. “You’ll know you can run faster.” But short races are also useful learning experiences. “[The] 5K requires a visceral sensitivity to what is too fast,” Derderian says.

And while marathons are slower, there’s still a cusp between ideal pace and going too fast. “You have to feel it,” Derderian says. “Racing is the best preparation for racing, particularly at race distances shorter than your ultimate race.”

University of Iowa head track and cross-country coach Layne Anderson agrees. “T am a firm believer that the faster you are—and feel—the more comfortable the marathon pace [will] be,” he says. In fact, he says of his star trainee, 2:29:54 marathoner Diane Nukuri-Johnson, “I even used a mile race during her preparation for Boston.”

But mile pace and 5K pace are only part of the speed-training equation. The third element is being able to go medium-fast: a pace now widely known as tempo running, or “threshold” running.

Three decades ago, a team of exercise physiologists led by Bertil Sjodin of Sweden’s National Defense Research Institute put eight experienced distance and middle-distance runners on treadmills.

At the start of the study, Sjdin’s team measured the runners’ blood chemistry at various paces, with a particular eye to lactate, a chemical long believed to correlate with racing performance. Then they asked the runners to incorporate weekly 20-minute workouts into their training schedules at a pace they called V,,,, ,~—the speed at which their tests had found an “onset of blood lactate accumulation.”

It wasn’t that no one had trained runners at roughly these paces before: Bill Bowerman and Bill Dellinger had long been doing something similar at the University of Oregon. But Sjédin’s team was the first to put it under the microscope, and their results, published in the June 1982 issue of the European Journal of Applied Physiology and Occupational Physiology (Sjédin, Jacobs, and Svedenhag 1982) hit the 1980s running community like a bombshell: after 14 weeks of the prescribed training, Sjédin’s runners saw their laboratory-measured V drop by 4 percent, from 5:43 per mile to 5:29.

OBLA paces

Suddenly, tempo runs became one of the linchpins of modern training. But there was just one problem. Sjédin’s study produced the conception that there is one perfect pace at which to do these runs—and that the best way was to find that perfect pace and stick to it for about three miles. And that just isn’t the case according to the latest exercise physiology … nor is it what many top runners, especially marathoners, are actually doing.

To understand the confusion, it’s useful to begin with an in-depth look at tempo-running physiology.

One of the reasons the focus has so strongly been on V,,, ,—and the 20-minute runs that are most appropriately run at that pace—is that V,,, , indeed appears to be an important predictor of racing performance. “It gives some idea of where someone’s ‘critical power’ is,” says exercise physiologist Halliwill, who describes this as “how intensely you can exercise for a sustained time.” V,,,, , is also one of the easiest performance parameters to change—much more responsive to training than VO,max, for example. (In fact, in Sjédin’s study, the runners’ VO,maxes didn’t budge.)

Daniels defines that power as about the pace you can hold in a one-hour race—for most of us somewhere between 10K and 15K. What this means is that in Sj6din’s study, the runners may have sped up not just their lab-measured V,,, , paces but their 15K times by an average of 14 seconds a mile. Extrapolate that to a marathon, and you’re looking at a potential six-minute gain.

Unfortunately, Sjédin’s study didn’t include before-and-after time trials. But in 2013 a team led by Jordan Santos-Concejero from the University of the Basque Country in northern Spain examined 22 nationally and internationally competitive runners, finding a strong correlation between V,,,, , and 10K times (Santos-Concejero et al. 2013). Specifically, the scientists’ data revealed that each 10 seconds per mile difference in V,,, , correlated to about a 70-second difference in 10K PRs. Extrapolating to the marathon, this would mean that Sjédin’s 14-second gain might translate to a seven-minute gain—and the Spanish study subjects were no slouches: their average 10K time was 31:35, roughly equivalent to a 2:30 marathon. At that level, six or seven minutes is a /ot.

Not that this proves that increasing your V_,,, , will make you faster. It might be that high V_,,, , is simply a consequence of being fast—the result rather than the cause. But studies like Santos-Concejero’s are why runners and coaches have long been interested in workouts at or around V,,,,, pace. As Iowa State coach Anderson puts it: “A hallmark for any great distance runner or aspiring runner is their ability to run at threshold pace.”

But there’s still a basic problem because not everyone has the same idea of precisely what running at (or around) threshold pace actually means. Resolving this confusion requires delving in some depth into the details of lactate metabolism.

Lactate myth and reality

Even before Sjédin’s study, lactate (sometimes mistakenly called lactic acid) was a chemical associated with running too far at “anaerobic” paces. At least as far back as 1924, Nobel laureate Archibald V. Hill (widely hailed as one of the pioneers of exercise physiology) had spotted the link (Hill, Long, and Lupton 1924). But in the process, it became a chemical with a bad reputation. Over the years, it’s been blamed for everything from sore muscles to the dead-legs feeling at the end of fast-paced intervals. But none of this is true. When scientists inject lactate into people, even when they’re already working hard on a treadmill, they don’t suddenly feel fatigued. “They do just fine,” Halliwill says.

In reality, lactate is simply a byproduct of glucose metabolism. “It’s roughly half of a glucose molecule and it still has a lot of energy we can use,” Halliwill says.

The association with “anaerobic” running comes from the fact that no oxygen is needed to break glucose down into lactate, but oxygen is needed to pry additional energy from it. This has led to the misconception that lactate is produced only under anaerobic conditions, but it’s actually produced any time you move a muscle—even if only to turn a page in this magazine. At low exercise levels, however, you have enough oxygen in your blood to burn it up nearly as quickly as it’s formed, which means that the amount making its way from the muscles into the blood is minuscule. At slightly higher exertion levels—walking, jogging, moderate-paced running—you produce lactate more quickly but you also use it up just as quickly because, again, your heart and lungs are providing as much oxygen as your muscles need, and your muscles have everything they need to burn up lactate as fast as needed. Because everything’s turning over at a faster metabolic rate, a bit more lactate finds its way into the blood, but not a lot.

Somewhere around marathon pace, things start to change. By this point, the lactate level in the blood has edged up to about 2 millimoles per liter (2 mmol). That’s still fairly low, but if you continue to speed up, the level will now rise more rapidly. By the time you’ve reached Daniels’s one-hour race pace, it’s doubled to 4 mmol. Above that it skyrockets toward zones mostly relevant to 400-meter or 800-meter runners (for whom half of their energy may come from their ability to maximize their lactate-producing “‘anaerobic” energy system).

Mounting levels of lactate may sound like a bad thing, but research says they aren’t. In a series of papers in the last couple of decades, George Brooks, an exercise physiologist at the University of California, Berkeley, has found that when lactate climbs in the bloodstream, the body uses the blood to ship that lactate away from the hard-working muscles where it is produced to better-oxygenated places where it can be used more effectively. One of these is the heart. Another is the brain. Even some lesser-working muscles, such as the arms, appear to be able to pull lactate out of the blood to use as their own fuel, saving glucose for the

muscles that really need it. The liver also gets into the act by using oxygen to help rebuild some of the lactate reaching it into glucose to ship back to the muscles.

This process, which Brooks calls the “lactate shuttle,” makes it possible for you to run faster because glucose, not lactate, is the body’s “high-octane” fuel. Rather than being a sign that our leg muscles are drowning in a performanceimpeding substance, the rise of lactate in the bloodstream means our bodies are shunting that lactate around to places where the power demands are lower, conserving glucose for the high-demand running muscles. “It helps establish a sort of hierarchy for glucose use,” Halliwill says. “The organs that most need it get priority and others rely on lactate.”

That said, rising lactate and increasing fatigue go hand in hand. Even if lactate isn’t the evil we once thought it was, training the body to use it more effectively (by postponing the point at which blood lactate starts to rise) will also postpone the point of fatigue, with the hope of running farther, faster.

That is what tempo running is designed to do.

Multiple “thresholds”

That’s the science. The application is less clear. In part, that’s because nobody but exercise physiologists use the term V,,,,. Coaches and runners prefer to speak in terms of lactate-threshold pace, threshold pace, or simply tempo runs. Worse, Pitre Bourdon, head of research at Qatar’s Aspire Academy for Sports Excellence, has found a long list of other terms, including “aerobic threshold,” “anaerobic threshold,” “aerobic-anaerobic threshold,” “lactate turn point,” and others too cumbersome to list here (Bourdon 2012). Further ratcheting up the confusion, some coaches have attempted to identify two distinct threshold paces, distinguishing them as lactate threshold and anaerobic threshold—teferred to by Bourdon as lactate threshold 1 (LT1) and lactate threshold 2 (LT2).

“I’m a big believer in lactate-threshold training,” says Paul Greer, coach of the San Diego Track Club, “but it does get confusing.”

The primary source of confusion may simply be the term threshold. It implies a magic pace at which lactate levels suddenly leap skyward, but that’s not how it works. Halliwill compares the lactate curve to a hockey stick, “although it’s a blurry, rounded-out hockey stick.” In other words, the magic threshold is anything but a threshold. It’s a vaguely defined zone in which lactate rises, but not instantaneously.

The result is that scientists can identify at least four distinct parts of the bend that can legitimately be labeled as lactate threshold, covering what for many of us might be a 20- to 40-second-per-mile pace range. The fastest (for most runners) is something we can call LT, 9: the level at which lactate hits 4.0 mmol per liter. It’s Sjodin’s Voy, , pace and (more or less) Bourdon’s LT2. The slowest is something

we can call LT\jisu. This is the point where the lactate curve first appears to start bending upward—basically Bourdon’s LT 1. Many coaches associate it with lactate levels of 2.0—2.5 mmol, but Bourdon puts it slightly below 2.0 mmol. For a lot of runners, it’s not far off from marathon pace.

The other two measures are a bit harder to explain. One is something that Bourdon calls LT pmax. Finding it requires looking at the entire “hockey stick” bend. You can then draw a line (a chord for those who remember their geometry) between the start of the bend and its end. The pace at which actual blood-lactate levels are most different from this chord (maximum Difference) represents the point of maximum curvature of the bend—a geometrically based measure of the threshold. In work with Australian rowers, Bourdon found that it comes in at slightly lower workloads than LT yo.

But there’s a final complication, because in addition to varying with speed, blood lactate changes with run duration. At moderate speeds, it spikes as you’re warming up, then declines. At higher paces, such as LT , it slowly rises as the tun progresses. Not surprisingly, there’s an intermediate pace at which it stays constant for 20 or 30 minutes—something that could be called LT sustainea- Ina 1993 paper in the Journal of Sports Sciences, a team led by Sissel Tomten of the Norwegian University of Sport and Physical Education, Oslo, found that this occurs at blood-lactate levels of about 3.0s (Borch et al. 1993). South African exercise physiologist Tim Noakes, author of Lore of Running (Noakes 2003), suggests that LT3 might therefore be the best measure of threshold pace.

In other words, if you want to run a tempo run, you’ ve got at least four “ideal” paces to choose from, which the scientists all identify on the basis of blood tests.

Luckily, the needed tests aren’t out of reach for the average athlete. Technological advances have produced cheap, portable, lactate-test units (similar to a diabetic’s glucose meter) that will allow you to draw a drop of blood from a fingertip anytime you want during a workout and give you your lactate level within a minute. Using these, Sean Coster, a Portland, Oregon, exercise physiologist, says you can determine your entire lactate-threshold curve in about an hour, either on a track or a treadmill. “All we have to do is to create a set of progressively faster runs,” he says. If you wear a heart rate monitor during the test, you can even calibrate the results to your heart rate.

Coster’s protocol involves four to seven three-minute repetitions, starting at moderate effort and progressing to 10K pace or faster, with one-minute rests. An all-out effort is never needed, though good pace control is useful if you’re not on a treadmill. Basically, it’s an easy interval session. Cost: “about $125 to $150,” Coster says.

Elite coach Brad Hudson recommends tracking your progress by doing such tests periodically. “Twice a year if you can,” he says, noting that it’s possible to combine it with a VO,max test. If you can do only one, he adds, “It’s more important to get your threshold tested.”

For some of us, of course, the idea of that many blood tests is more terrifying than a marathon. Not to mention that even if it’s a lot cheaper than it used to be, it still exceeds the cost of a new pair of shoes.

Luckily, there are other ways to get yourself into the right pace range. One is simply experience and feel. Olympic coach Alberto Salazar once described the classic 20-minute pace as “fun fast.” Liana Bernard, a former 10K All-American who later clocked a 2:42 marathon, describes it as “running hard, but not to the breaking point.” Iowa coach Anderson says it “feels like a 75 percent effort… comfortably hard. You don’t want it so fast it becomes a time trial, nor so slow it’s no more than a glorified recovery run.”

Other ways to estimate the right pace include:

¢ Daniels’s definition: your pace in a race lasting approximately one hour, whatever distance that is for you.

* Conconi test. Based on a 1982 paper in the Journal of Applied Physiology by a team led by Italian biomedical researcher Francesco Conconi (Conconi et al. 1982), this test is conducted with a heart rate monitor. The idea is simple. At slow-to-moderate paces, heart rate increases linearly with pace. But there comes a point where it starts to level off, no matter how fast you run. The point where this occurs, Conconi suggested, is the lactate threshold.

¢ VDOT tables. At least as far back as 1979, Daniels and his one-time associate, Jimmy Gilbert, created charts that used current race performances at a wide range of distances to create a ““WDOT” measure (somewhat akin to VO,max, although also accounting for running economy) that can serve as a metric of your current racing ability. Based on that, tables in Daniels’s book suggest training paces, including threshold pace.

¢ 3,200-meter time trial. In a 1987 study in the /nternational Journal of

Sports Medicine, a team spearheaded by University of Virginia researcher Arthur Weltman (Weltman et al. 1987) attempted to correlate 3,200-meter time-trial paces with laboratory-measured lactate-turnover paces, producing threshold paces substantially faster than those from Daniels’s VDOT tables. (An 11:56 3,200-meter time trial, for example—equivalent to 12:00 for two miles—gives a threshold pace of 6:10 per mile, while Daniels’s VDOT tables put the proper pace at 6:32.) For those wanting to try it, Weltman’s formula is:

Vip = 509.5 — 20.82 X tyr00m

where v,, is threshold pace (in meters per minute), and t,,5,, is the

3,200-meter time in minutes. (Converting this into a traditional

pace measure is not the simplest of calculations.)

¢ 30-minute time trial. Like the Conconi test, this one is also heart-rate based. In a 2000 article in Inside Triathlon, cycling and triathlon coach Joe Friel (Friel 2000) argued that all it takes to find your lactate-threshold effort level is to monitor your heart rate during a 30-minute solo time trial—with the emphasis on solo. “Doing this as part of a race or with training partners will change the outcome,” he says on his blog. During the first 10 minutes, your heart rate will rise toward the lactate-threshold plateau, but it’s the average heart rate during the final 20 minutes that matters. Friel adds that if you do the test in a race setting or with pacers, it needs to extend to 60 minutes—exactly paralleling Daniels’s classic definition.

Which is best? In a 2005 study in the Journal of Strength and Conditioning Research, ateam led by Joseph Houmard, an exercise physiologist at East Carolina University, Greenville, North Carolina, had 27 distance runners and triathletes do the last four of these tests, then compared them to lactate blood-work determined on a treadmill (McGehee, Tanner, and Houmard 2005). Their conclusion: forget the 3,200-meter time trial and the Conconi test. Both gave paces at least 10 percent too fast. The best was the 30-minute solo time trial, with the VDOT tables not far behind.

Predator runs, new intervals, and alternations

The idea of threshold training is that pushing the body at this pace will make its lactate processes more efficient at all speeds. In essence, this should shift the entire lactate curve outward, allowing you to run farther, faster—even at the marathon. But it’s not rocket science, not to mention that exercise physiologists really don’t know why running at or near this pace (however it’s defined) might make lactate processes more efficient.

“A lot is based on coaches’ experiences and anecdote,” says Halliwill. “What we can say is that when people train through a variety of approaches, whether it is lactate threshold specifically or interval training at higher intensity, we see that critical pace—that threshold—shift out to higher intensities of exercise.”

Some coaches, in fact, aren’t even sure training precisely at threshold is worth aiming for. In his new book, Running Science, Owen Anderson (Anderson 2013) notes that lactate levels can vary with everything from how much sleep you had last night to what you had for lunch. British coach Peter Thompson, now residing in Eugene, Oregon, takes it a step further. “Threshold varies daily,” he says. “It’s almost an obfuscation. Some coaches pick out threshold as a crucial thing, but it’s a consequence of a program where other factors are [also] taken care of.”

Still, most coaches, especially marathon coaches, rely heavily on threshold training of one form or another. But even for them, Anderson’s and Thompson’s caveats underscore that the name of the game isn’t dialing in too obsessively on

a specific pace. It’s likely that any workout that carries you through the threshold zone without overtaxing you might be beneficial. For collegiate distance runners, for example, Corey Ihmels, who coached Olympic 10K runner Lisa Uhl to fame and is now head coach at Boise State, often works via progression runs and twomile cutdowns. “‘We start at a conversational pace, then build,” he says, noting that for men, these might extend eight to 10 miles and for women six to eight miles. “At some point the kids will hit threshold,” he says.

Scott Simmons, coach of the American Distance Project in Colorado Springs, Colorado, adds that traditional threshold runs don’t actually mimic racing anyway, because in racing you’re rarely precisely at threshold. The marathon is too long to run that fast. And for shorter races, “whether it’s the mile or the half-marathon, you’re actually pushing through that threshold because that’s what the competition demands: to push through and run as fast as you can on the other side.”

Traditional steady-paced tempo running, he says, isn’t supereffective at achieving this goal. “It’s better than not doing anything, but it’s not the best.” Thus, like Thmels, Simmons is a fan of progression runs, which might start out a minute a mile slower than current 10K pace (slower than marathon pace for most people), then speed up, mile by mile. “We call them predator runs,” he says: “[It’s] how a predator will increase tempo to catch prey, especially as they get close.” He warns, though, that these runs shouldn’t be extraordinarily intense. “It’s not that extreme a workout,” he says. “We don’t want the training to be a race.”

Another approach comes from Thompson, who calls it “new interval training.” It’s based on using perceived effort to yo-yo lactate levels up and down by doing sets in which you alternate between slightly faster than traditional threshold pace and slightly slower: in essence, training the body to deal with, then quickly recover from, the conditions that produce elevated lactate. (Elite coach Renato Canova, who works with some of the world’s top Kenyans, calls these “alternations” and, for elite, high-mileage marathoners, has been known to put as many as 24 kilometers of them in a single workout.)

Hudson also believes in variety. “There’s a lot of different runs you can do,” he says. “I think there’s a misconception that all tempo runs are done at a 4 mmol lactate level… . Three X 3 miles can be done at 2, 3, or 4 mmol.”

Putting all of this together for marathon training is a daunting task—but no more so than the race itself. But the fact is that if you want to find your best marathon, it’s no longer good enough just to be able to endure. You also need to find your speed, whether by putting the final touches on your VO,max, improving your running economy, improving your lactate shuttle via Thompson’s new interval training or Canova’s “alternations,” doing predator runs to help get you through the final 10K, or doing long tempos at marathon pace.

How to apply this, however, is highly individual. As a coach, I’ve seen good results from all of these. One woman made a multiyear dream of qualifying for

Boston off a regimen that began with speed workouts more suitable for an 800meter runner, followed by workouts that progressed to five miles of Canovastyle 800-meter and 1,000-meter alternations in which the pace varied between half-marathon pace and faster-than-10K pace. Another peaks beautifully on such workouts as 10 X 2K at half-marathon pace, culminating in a 20-mile predator run. But every few weeks she has to do some fast 200s or 400s, or her efficiency on longer runs falls apart. (Please note that both of these runners were comfortable at 60-80 miles a week. Speed is good, but base still affects how much of it you can do.)

The point is that there are no magic-bullet workouts that work for everyone. So run fast/short. Work on VO,max. Try Billat intervals. Do a few classic 20-minute tempo runs. Do two-mile cutdowns, Canova alternations, Thompson’s new interval training. Mix it up, because the only thing I know for sure is that if you do the same speed workout, week after week, you’ll almost certainly stagnate.

If you’re really desperate for formulas, remember that part of training is periodization, in which you slowly build from base into peak shape. Marathoners have long been taught how to do this with long runs and mileage buildups. But it also applies to speed, and for that, the optimal peaking program might be as much as twice as long as the 12-16 weeks of traditional marathon training.

A fairly standard way to begin is with base. When ready, build into a focus on speed (VO,max or vVO,max), perhaps running a few short races. The Bostonqualifying runner I mentioned earlier set PRs at the 800 and the mile (and the 200, 400, 5K, and half-marathon) en route to her marathon triumph. Then, when the time comes to focus on ramping up for the marathon, shift the primary speed emphasis to lactate, but not so thoroughly that you lose too much of your hardwon speed and efficiency.

How exactly to combine all of this into a perfect peaking program is beyond the scope of this article. What matters is that if you do it right for your particular body (and if you don’t overdo it and overtrain), it can all come together in a rather startling PR.

But ultimately, part of the process lies in Simmons’s idea of turning yourself into the predator. When I started working on this article, I asked my friend Bob Williams, former Pac 10 steeplechase champion and distance coach at Concordia University (Portland), about speed work, especially tempo runs. After several minutes of searching for the perfect answer, he asked me to turn my voice recorder back on. “It helps the athlete feel that sense of toughness that they experience when they compete,” he said. “I think it’s a process of adaptation, psychological as well as physiological.”

In other words, run long to learn how to endure. Run faster to learn a different type of toughness. Combine them on race day, and your brain and body may collaborate to give you the triumph of your dreams.