Taken from an article in Runners World by Kevin Beck
If you toss around the term “tempo run,” it’s pretty clear that you’re serious about your sport. But while a tempo run is a key staple in the training diet, very few people actually know what exactly the recipe calls for.
In fact, there’s a lot of misconceptions about the tempo run. Take, for instance, the guy who finishes a road race completely out of gas, slumping over the fence to catch his breath.
Despite his hard effort, when asked how he feels about his race—which may have resulted in a time a bit slower than his goal—he says with a dismissive wave, “Ahhh, I ended up basically doing a tempo run.”
Here’s the problem: Mislabeling a sub-par race performance a “tempo run” is not just a matter of nit-picking semantics. Racing and tempo running differ greatly, and doing the latter incorrectly can compromise its training benefits. But learning how to incorporate it into your running routine can bring you lasting benefits—especially on race day. Here’s everything you need to know about the tempo run.
How to Find Your Tempo Run Pace
So what is a true tempo run? A tempo run—also known as an anaerobic threshold or lactate-threshold run—is a pace about 25 to 30 seconds per mile slower than your current 5K race pace, according to running coach Jack Daniels, Ph.D., who popularized the tempo run in his book Daniels’ Running Formula.
Without getting too technical, tempo pace is the effort level at which your body is able to clear as much lactate—a byproduct of burning carbohydrates—as it produces. Your body’s lactate clearance is at the same level as its lactate production, meaning the dreaded dead-leg sensation doesn’t set in.
That’s the key difference between a race and a tempo run. In an all-out session, your body bypasses this limit, allowing for fatigue to develop rapidly. A tempo pace, on the other hand, can be held steadily (albeit not too comfortably) for at least 20 minutes.
For those fond of using heart rate monitors, Daniels notes that tempo runs should be done at 90 percent of maximum and feel “comfortably hard.”
How Tempo Runs Help You Get Faster
According to exercise physiologist and coach Pete Pfitzinger, not all competitors benefit equally from tempo runs.
“Athletes racing from 15K on up to the marathon receive the most benefit from tempo runs because the physiological adaptations are most specific to the demands of those races,” he says. “An improvement in lactate threshold is only a small benefit for a 5K race, because it’s run well above lactate-threshold pace.” In longer distances, however, your performance is determined primarily by your lactate-threshold pace. So tempo runs provide a direct benefit in longer races for beginners and elites alike.