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When it comes to speed work, mile repeats might seem pretty set in stone. They don’t have the spontaneity of fluid workouts like a fartlek or even the varied intervals of, say, a pyramid workout—after all, like the name suggests, each and every repeat is exactly the same distance.
But really, there’s no one way to run the mile—and structuring this workout is way more versatile than you might think. “Mile repeats can be helpful in training for any race, any goal—from a 5K to a marathon,” says April Gatlin, ACE-certified personal trainer, master trainer and coach for STRIDE Fitness. All you have to do is vary the number of reps, the rest periods in between, and your intensity and you can tap into different energy systems and prep your body for any distance—and they might even help you hit a PR in that distance.
Here’s more about why mile repeats workouts are so useful, no matter your reasons for running, plus two ways to add the workout into your routine.
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What are mile repeats?
Mile repeats workouts are a type of speed workout that begins with a warmup followed by some number of repetitions of a single mile, with a period of recovery after each of those miles. “By simply changing the rest between each mile, as well as increasing or decreasing the paces, mile repeats can serve multiple purposes and work every energy system you’ll use during any race,” Juli Benson, Olympian and owner of Philadelphia-based Juli Benson Training tells Runner’s World.
You’ll likely want to run this workout on a track, since the terrain is totally flat and the precise measurement of each loop leaves no guesswork about when you’re finishing each interval. But you can do them anywhere (especially if you’re wearing a smartwatch that tells you in real time when you hit each mile)—and you might even prefer to go off-road if you’re gearing up for a trail race or just running for fitness.
What are the benefits of mile repeat workouts?
Depending on how you structure your mile repeats, they can improve different aspects of your running. One key benefit is getting faster. If that’s your aim, using your repeats as a VO2 max workout should be the goal—these are quite challenging and are meant to improve your body’s ability to deliver oxygen, explains Benson. In other words, they make you speedier by making hard running feel easier.
When doing mile repeats to work your VO2 max, you’ll do fewer reps (think two to four) at a quick pace with long rest breaks (about half the time it takes you to run each mile) to bring your heart rate down.
Another big takeaway from mile repeats: You can improve your stamina. To do that, your mile-repeat workout should push your lactate threshold, and to do it, you’ll aim for a tempo or threshold pace (a.k.a. a speed you can maintain for about an hour). “I like to use mile repeats early in a training cycle to prepare runners for longer, sustained threshold running,” says Benson.
To target the threshold energy system, or the level at which lactate accumulates in your blood, you’ll use short recovery periods and run each mile at a pace that’s closer to your half-marathon effort, she explains.
Although they’re fairly short intervals, mile repeats are long enough that they can help teach you what it feels like to hold your goal race pace, too—so you’ll be more prepared to stick with it come race day. They also help train your brain to stick with your goal pace when the going gets tough. “Pushing through mile repeats ups your mental fortitude, which can help you power through discomfort you’ll inevitably come across during long runs and distance races,” says Gatlin.
How do you add mile repeats to your training schedule?
First, make sure you have a good base of weekly mileage before adding new speed work to your routine. If you have a 5K on the calendar, your mile-repeat workouts should include just two or three reps. If gearing up for a half marathon or longer, you’ll want to add the intervals until you hit at least four to eight reps, increasing by one rep each week.
When you start incorporating mile repeats in your training schedule depends on the race distance you’re training for, says Gatlin. If prepping for a 5K or 10K, start these repeats three to six weeks before race day; the longer the race, the sooner you should start doing mile repeats.
Next, figure out the right pace based on your workout goal. Also, note that going out too fast will make it challenging to be consistent, says Gatlin. Ideally, you’ll be picking up your pace slightly with each mile interval.
Last, make sure you don’t skip the easy stuff. Of course pushing to maintain your goal pace is an important aspect of a mile-repeat workout. But easing into the slower-paced sections (i.e., your warmup and rest breaks between intervals) is just as crucial for reaping the most benefits.
“The most important aspect of this speed work is that you’re properly warmed up prior to starting the mile repeats, and also recovering in between repeats,” says Gatlin. She recommends starting by raising the body temperature with a light jog, then doing a few dynamic stretches and mobility drills to increase blood flow before you dive into your miles.
2 Mile Repeats Workouts to Try
VO2 Max Mile Repeats
After a warmup, do 2-4 mile repeats, resting for 3-5 minutes between each.
Run the first mile slightly faster than your 10K race pace, then increase your pace a bit with each repeat until the last mile is just slower than your 5K race pace.
Threshold Mile Repeats
After a warmup, do 4-8 mile repeats, resting 1 minute between each.
Run each mile at approximately your half-marathon pace. If you’re pacing these correctly, you should feel like you could handle one to two more repeats at the end.
