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How to properly pace a marathon

2011 Virginia Beach Rock n' Roll Half Marathon

Ask five runners how best to pace a marathon and you’ll likely get five different responses.

“Even pacing.” “Run a negative split.” “Start slow, finish fast.” “Use a heart rate monitor.” “Use your Garmin.”

Running and racing 42.2K is a difficult task. Few ever practice running the time or distance it takes to do it — for good reason — and thus don’t have any idea how long a marathon might take them. Even experienced runners who have run marathons before are hard pressed to predict their finish times.

Predicting the time it could take might involve running a shorter race — preferably a half-marathon three to four weeks before your race — and using the result and online running calculators to predict a range of probable finish times based on your current fitness. Our advice: have a realistic and attainable time goal in mind.

But even if you do have a goal time and pace in mind, how you choose to run the race can affect the results.

Do you start slow and pick up the pace as the race goes on? Do you try to run an even pace throughout the race? Or do you bank time in the first half and hold on for dear life? Thanks to heart rate monitors, GPS watches and other gadgets, obsessing over real-time data has never been easier, but what does it tell you and does it actually make us faster?

Over a year ago, an interesting study was published which highlighted an all-too-common and unsurprising trend in the marathon: runners generally slow down in the second half of the race and finish much slower than they start. What wasn’t expected however, was that the data indicated that most runners began to slow down right around the halfway point, which is much earlier than many would expect. Most runners don’t hit the wall until around 30K when the body’s carbohydrates begin to run out. Yet these runners were slowing down well before that.

Why do so many runners start to slow down so early and with still so much distance to go?

In many cases, runners start too quickly. They are rested, fully fuelled and pumped up on adrenaline, making it difficult to hold back, but even running several seconds faster than race pace for a few kilometres can be detrimental and slow you down later on. Our advice: start slow and take the first kilometre or two to settle into race pace.

Another likely scenario is that many runners are basing their early pacing and efforts on benchmarks they’ve set and data they expect to follow. They try to maintain a given pace, keep their heart rate at a specific level or aim to hit the halfway mark in a set time. The problem with this approach is that it doesn’t account for what happens later on.

A much better approach, yet one that is incredibly difficult to mandate, is to simply run by feel. Listen to the body and run at the pace that is dictated by the brain, which moderates the state and survival of all other organs and body systems. Running by perceived effort, regardless of pace, also accounts for environmental conditions and course variations such as hills, turns and terrain. Our advice: ignore the watch, at least for the first half of the race. You’ll be amazed to find that the body is able to run at the pace best suited for the conditions and, in most cases, will help you finish faster.

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