Have you ever turned a corner in a race only to see a long stretch of road or trail that is all uphill? Would your finish time be better if you knew about the hill beforehand and doled out your effort accordingly, or would you run faster if you learned about the hill only upon first seeing it?

That’s the question underlying new research about how runners pace themselves when they do and don’t anticipate upcoming difficulties, to be published in Medicine & Science in Sports & Exercise. The findings suggest that, to run your fastest, ignorance can be bliss – up to a point.

A Flat Out Falsehood

The study had an ingenious and dastardly design. First, 28 experienced runners did a 3,000-metre time trial on a treadmill set at 0 percent for an incline. Then each runner did two more 3K treadmill time trials. For one, the runners were told that the first 2,200 metres would be flat and that the treadmill would rise to a 7 percent grade for the final 800 metres. (The runners were told to expect “a steep slope.”) For the other, the runners were told that the treadmill would remain flat the entire time, as had been the case in the initial test.

The twist: The researchers lied in describing the final scenario. While anticipating they were running a flat 3K, the runners would instead encounter the same 7 percent grade for the final 800 metres. The researchers measured the runners’ intermediate and final times, and variables such as heart rate and rating of perceived exertion.

So, when the runners ran the early part of a time trial thinking they’d be on flat terrain the whole time, but then unexpectedly climbed a huge hill for the final stretch, their times had to be worse than when they knew what was coming, right?

Not at all. In fact, on average the runners finished 14 seconds faster when they didn’t know the last 800 metres would be uphill compared to when they knew the hill was coming.

Almost all of that 14-second difference came in the flat first 2,200 metres; the runners covered the final uphill 800 metres in roughly the same time regardless of how fast they ran the initial flat section. Adding to the intrigue is that when the runners knew the hill was coming, their heart rates and perceived effort were similar to when they didn’t know the hill was coming – even though in the first scenario they were running almost 8 seconds per 1.5km slower.

Is Ignorance Really Bliss?

Is it really better not to know what lies ahead of you on a challenging run? Yes and no.

Yes, in that it’s undeniable that the runners in this study produced faster finish times when they didn’t think their course included a big hill at the finish. And remember, their heart rates and perceived effort were similar at this faster pace compared to when they anticipated the hill. When they knew the hill was coming, the runners’ self-protective tendencies made them slower while making the run feel just as hard.
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This phenomenon is behind the old coaching trick of having runners think they’ve finished a hard workout, but springing one or two more repeats on them. The idea is that runners will do the workout without holding something back for the end, thus learning they could do more than they thought possible. As former marathon world record-holder Paul Tergat once said, “Ask yourself, ‘Can I give more?’ The answer is almost always yes.”

What the runners thought about when they didn’t know the hill was coming likely explains their superior performance in that time trial, lead researcher Noel Brick, Ph.D., told Runner’s World.

“Runners tended to focus on relaxation more during the initial stages of the unknown-incline trial than the known-incline trial,” he said. “We know that relaxation helps to improve running economy, so it is possible that running in a more relaxed manner also impacted on heart rate.” In contrast, when the runners knew the hill was coming, they fixated on their current perceived effort to gauge the right pace. “Focusing more on these feelings can make any given pace feel harder,” Brick said.

When the runners found themselves unexpectedly climbing, they navigated the challenge with motivational self-talk such as, “You can do this” or “Keep going.” Brick said having these psychological tools is key. “Not knowing what is ahead can be beneficial, but only if you have the mental skills to cope when something unexpected happens,” he says.

On the other hand, there are times when you’re better off knowing what’s ahead. You probably won’t run your best Soweto Marathon by tearing through the downhill first half unaware of the final hills towards the end of the race. Brick suggests two key strategies for getting the benefit of knowing what’s head without having it detract from your performance.

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First, reduce uncertainty about anticipated difficulty. For example, if you’re going to go to the trouble of researching a race course, then get relevant real-world experience. Train on similar terrain “so that you know exactly what is ahead of you and how you will cope with the demands it presents,” Brick said.

Second, while being mindful of a challenge ahead, keep your attention on the segment of the course you’re running.

“Chunking, or mentally breaking the course into separate parts, can be helpful,” Brick said. “Focus on one chunk at a time, like the first five kilometres, then the next five, etc.

“Also, set shorter-term goals for each of these chunks,” he said. “These goals might not only relate to a pace or time for each chunk, but also a process for running each. In the first five kilometres, the process might be to focus on remaining as relaxed as possible, or to stick with a pacer who is pace-setting for your target time.”

Or, as the bracelets put it, run the kilometre you’re in.

This article originally appeared on runnersworld.com.

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