Respected running and fitness expert Matt Fitzgerald has agreed to share with Rundamentalists readers a revolutionary training method used by the ‘elites’ to achieve extraordinary results. Matt is proposing that we will run stronger and race faster by training slower!
Are You Stuck in the Moderate-Intensity Rut?
Guest Post by Matt Fitzgerald
Every runner has a natural running pace. This is the pace you automatically settle into when you do an unstructured run of a given distance (e.g. 5 miles) or duration (e.g. 45 minutes). There is some degree of variation, of course. You might run a little faster on a day when you feel fresh than you do on a day when you feel sluggish and a little slower on a hot day than you do on a cool day, but chances are you will run at almost exactly the same pace in your next “easy run” as you did in your last one, without consciously intending to.
What determines a runner’s natural pace? Research suggests it is regulated by perceived effort. In a 2012 study, for example, experienced female runners were asked to run on a treadmill for 30 minutes at a self-selected pace. During the run, the subjects were asked to rate their effort level on the Borg Scale of Perceived Exertion, which goes from 6 to 20. The runners gave an average rating of 12.79, which happens to fall smack in the middle of that 6-20 scale. What’s more, the standard deviation for these ratings was a low 1.15, meaning all of the women gave ratings very close to the 12.79 average.
There is a striking consistency in the results of studies of this type. People of both genders, all ages, and various levels of fitness automatically settle into a moderate effort level corresponding to roughly 12.5 on the Borg Scale when performing any type of aerobic exercise. In 2001, researchers at Wayne State University asked college students to exercise for 20 minutes at a self-selected intensity on each of three pieces of cardio equipment: a stationary bike, a stair climber, and a treadmill. Their average rating of perceived effort was 12.5 on all three.
This begs the next question: Why does everyone automatically perform cardio exercise at the same moderate intensity? This question has not been answered scientifically, but I have a theory. When you go out for an unstructured run of a given distance, you have two competing objectives: One is to get the run over with, which pushes you to go faster; the other is to not suffer inordinately, which impels you to run slower. When you compromise between these competing objectives, you choose a moderate intensity.
For additional guidance on breaking out
of the moderate-intensity rut, check out
Matt's book, 80/20 Running.
Of course, most runners who are serious enough to participate in races and aim to improve their times do not run at moderate intensity all the time. They do different kinds of runs that target different intensities. But research has also shown that most runners in the “recreationally competitive” category spend a lot more time at moderate intensity and a lot less time at other intensities than they think they do.
A 1993 study by researchers at Arizona State University found that recreationally competitive runners spent 46 percent of their total weekly training time in this moderate zone of intensity, another 46 percent at low intensity, and the remaining 8 percent at high intensity.
Other studies have yielded similar findings. So it appears that an approximate “50/50” intensity split—where half of total training time is spent at moderate intensity and half at other intensities—is the norm. This is a problem, because a number of recent studies have demonstrated that runners improve most when they do 80 percent of their training at low intensity and only 20 percent at moderate to high intensity. In one such study, runners maintained either an 80/20 or a 65/35 intensity split for five months. Both groups improved their performance in a 10.4-km time trial, but the runners in the 80/20 group improved 30 percent more.
Taken together, all of this science suggests that getting caught in the “moderate-intensity rut” is the most common and costly mistake that runners make in their training. If you’re like most runners below the elite level, you are making this mistake, and it’s holding you back. The good news is that fixing it is easy—in fact, making your training easier is precisely how to fix it.
Step one is to learn the differences between low, moderate, and high intensity. Most runners think they are running at low intensity when in fact they are running at moderate intensity. You need to recalibrate your sense of effort to escape the moderate-intensity rut.
Step two is to plan your training so that 80 percent of your running is done at low intensity and the remaining 20 percent of your training is divided between moderate and high intensity. Finally, you need to actively monitor your intensity by perceived effort, pace, and/or heart rate in every run to ensure that your 80/20 training plan is executed correctly.
"Learn the differences between low, moderate, and high intensity."