The idea of running negative splits has been so ingrained in us, it’s as rudimentary of a skill for runners as tying your shoes. At some point, every runner needs to learn how to run negative splits or figuratively die trying.

By definition, a negative split is when the second half of your run or race is faster than your first half. The ability to run negative splits teaches you how to manage your energy and pace yourself properly throughout a race or training run. This is ideal because you learn how hard you can push early so you won’t blow up during the second half.

But just as every coin has two sides, so does pacing. On the flip side of negative splits are positive splits. This is where you go out faster and slow down as the run or race goes on.​ Considered taboo, prevailing wisdom warns against intentionally running positive splits. Positive splits are thought to be associated with pain, embarrassment, and bad outcomes.

However, I think most gamblers would agree that sometimes a calculated move against the prevailing odds can pay out big time. And as certified run coach and runner myself, I think when executed properly, the positive split can be a powerful pacing strategy. One that might just get you that personal record or Boston qualifying time you’ve been working so hard to finally snag. But here's what to know before you start your next run or race on the faster side of your goal pace.

Should you ditch a negative split goal?

The elusive negative split is perhaps as much of a goal in running as setting a personal best. We see the elites do it all the time and it has been well documented that most world records are set with negative splits. But what about the rest of us who aren’t breaking world records? Are there scenarios where one should ditch a negative split? I would say yes.

Justin Ross, Psy.D., a clinical psychologist specializing in health and wellness psychology, human performance, and sports psychology agrees. A runner himself, Dr. Ross explains, “elites are really good at running 26 miles because they've been running 100 plus miles a week for a long time, versus amateurs who just can't maintain that pace for that long of a period because we don't have the training or maybe even the physiological capacity.”

This brings up the question: If we amateurs aren’t running 100 plus miles a week and may not have a superior physiological capacity, should we be mimicking the elites’ negative split pacing strategy? While I do believe the more experienced runners should seek to follow their faster counterparts, I want to offer an alternative for the non-elites. That is, something I call the “controlled fade.”

What is a controlled fade?

The controlled fade is a deliberate, positive-split pacing strategy—one that is calculated and won’t lead to blowing up or hitting the wall. It’s a slow, gradual fade in pace. “I don't think we need to fear the positive split if it's done with intention and reason and that the slow fade is really close—like within relatively even splits,” explains Dr. Ross.

Note Dr. Ross’ words “done with intention and reason.” For a controlled fade to be successful, it needs to be a calculated strategy. Dr. Ross warns, “I don’t think we need to be afraid of the positive split, but I do think we need to be careful of it.” This is because the margin for a blowup is much greater than with a negative split strategy. If you’re too ambitious during the first half, a controlled fade will result in a disastrous second half, potentially one that leaves you dragging or walking or just straight up miserable for those latter miles. On the other hand, if executed properly, it can be highly successful.

What’s the benefit of skipping a negative split?

“I think a big part of this is a mindset shift that you don't have to negative split to run a PR,” says Dr. Ross, who set his marathon personal record of 2:57:36 at the 2019 California International Marathon by running 86 seconds faster in the first half of his race—coincidently a positive split.

Mentally, there is a very different mindset between having to pick up the pace at mile 20 to reach your goal when you're already tired versus having time in the bank to fade a little. With the latter, you've met your goal and it's yours to lose and with the former, you don't have the goal and need to chase it when you're already tired. People are more likely to fight to hold onto something they already have than something they never had in the first place.

So that benefit to a controlled fade? It comes down to a pretty positive mental approach to those latter miles—and of course, it could also pay off with a faster finish time.

How do you properly execute the controlled fade?

Being honest about your current fitness is crucial for the successful execution of the controlled fade. The best way to get an honest assessment of your capabilities over all race distances is to plug a recent race result into a running pace calculator that projects what an equivalent performance would be across other distances. This will give you an idea of what you are capable of if all things go perfectly on race day.

In most cases, a more realistic goal is to add two to five minutes to what calculators tell you, especially if you’re using race times further away from the marathon such as a 5k time. If your goal falls within that two- to five-minute window, it’s likely to be attainable and suitable for the controlled fade strategy.

A controlled fade works best when you run the first half of your race between a total of 30 seconds and three minutes faster than the second half. This equates to five to ten seconds per mile for the marathon. When pacing the first half of a marathon, aim for five seconds per mile faster than the goal finishing time pace with an absolute speed limit of 10 seconds per mile faster. For example, if you’re trying to break 3:30 for the marathon or run an average 8:00/mile, aim to run the first half at a 7:55/mile pace, never to exceed a 7:50/mile.

The goal is to maintain this pace for as long as you can, expecting you’ll fade at some point. The deeper into the race you hold the pace, the more of a buffer you’ll build against your goal finishing time.

Keep in mind, it’s still important to ease into that faster pace. So starting 10 seconds slower than the goal pace for the first mile may be a good option for some who need a warmup mile. You’ll make up that time by mile four or five if you settle into your planned controlled fade pace by mile two.

When should you use a controlled fade?

A controlled fade works best for longer races, such as the marathon, and when there’s a lot of internal pressure to beat a very specific time.

To determine when to use a controlled fade, it comes down to your goals. Dr. Ross points out the difference between outcome goals and performance standards. Outcome goals are a specific outcome you’re pursuing, such as breaking your personal record or qualifying for the Boston Marathon, whereas performance standards are “more about the approach you take to showing up.” For outcome goals, there is a clear delineation between success and failure. You either hit your goal, or you don’t.

“Often what will happen in the course of a race is we recognize that our outcome goals are out the window for whatever reason—the weather isn't cooperating or it's just not our day. At that moment in time, often runners get really defeated and they get frustrated,” Dr. Ross says. Without having a performance standard to fall back on, some runners might give up and completely abandon their goal.

That’s where the controlled fade comes in: Building a small cushion of time to fall back on late in the race allows runners who place a heavy emphasis on outcome goals some room for error, alleviating some of the pressure.

So think about what you want to achieve in your run or if you have that specific goal to chase in your race and whether the controlled fade would work for you.

What do other coaches say?

Terry Howell, owner of Blue Collar Running, has coached seven runners to the 2020 Olympic Trials. He agrees the controlled fade is a viable plan for some runners and often builds in a cushion, even for his elite runners. “Depending on the caliber of the athlete, and the condition they’re in, I'm okay with a two-minute cushion on the backside, meaning going slower in the second half.” In an ideal situation, Howell likes to see his athletes somewhere between 30 seconds slower and 30 seconds faster than their goal marathon pace at the halfway point.

On the other hand, Karen Dunn, owner of Strengthen Your Stride and VDOT certified distance coach and RRCA level two run coach, says “it really comes down to knowing your athlete, knowing their history, goals, and mental strength and tenacity.” She believes that an even pace, or slightly negative is the best strategy, but does acknowledge if it’s the right person, a positive split may help some gain confidence.

Is a controlled fade the right approach for you?

At the end of the day, it’s important to steer clear of absolutes. When it comes to a negative-, positive-, or even-split pacing strategy one isn’t always better than the other. It all boils down to the individual runner, race course, and what feels comfortable in a given situation.

However, the only way to find out if one pacing strategy is better for your particular situation is to try it out. If you’re like most runners who have been wired to believe positive splits are synonymous with poor performances, give the controlled fade a try. It could pay off even more than you expect.

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Cory Smith

Cory Smith is a running coach and journalist specializing in running and fitness-related content and gear reviews. He is the founder of Run Your Personal Best, an online running coaching business that has helped hundreds of runners achieve personal bests in distances ranging from 800 meters to 100 miles. Cory holds a USA Track & Field Level 1 and 2 Endurance Certification and was the former Head Cross Country/Track Coach at Penn State Brandywine. Over his running career, Cory has held three Maryland state records, was a two-time National Championship qualifier while at Villanova University, and holds personal bests of 4:03 in the mile and an 8:05 in the 3K.