Most solid training plans include a weekly speed workout, often in the form of intervals. But the length of those intervals usually depends on your race distance, training goals, Why You Need Both Long and Short Intervals.
The way you approach 200-meter repeats likely won’t look the same as two-mile repeats, so we spoke with experts to reveal the subtle differences in short versus long intervals, including how to execute them, the benefits of both, and whether or not you should stick to one or the other.
Warm up for 1 mile at zone 2 easy pace
Both long and short interval workouts improve cardiorespiratory fitness and muscle-fiber recruitment, according to Laura Norris, You’ll also typically take longer rests between short intervals due to their.
That muscle recruitment pays off big time when you’re vying for a PR. “When you’re in a race and you’re trying to run fast, or you’re trying to run on fatigued legs at the end of a marathon, your body then knows how to recruit more muscle fibers,” meaning you can push hard paces for longer efforts, Norris explains.
As for the cardio fitness payoff, intervals improve your maximum cardiac output, or how much blood your heart pumps to send to your working muscles, Norris explains. This allows your working muscles to get more oxygen, which can boost VO2 max and improve performance.
Research backs up the benefits of interval workouts: A 2021 review published in the International Journal of Environmental Research and Public Health examined studies from the last century involving different forms of high-intensity interval workouts—with work periods ranging anywhere from 10 seconds to four minutes, aiming for a near maximal effort, and rest or recovery intervals spanning the same time frame—as well as 30- to 60-minute sessions of moderate aerobic training.
The researchers found that, compared to moderate-intensity training, interval workouts led to greater improvements in VO2 max, motor unit recruitment, capillary density, and red blood cell volume and hemoglobin (which allows for higher oxygen carrying capacity). All these payoffs contribute to a more robust aerobic engine and better running economy.
Additionally, a recent study published in Frontiers of Physiology recruited a group of 20 male distance runners and randomly assigned a group to sprint interval training, while another group stuck to their typical distance training. After 100-meter, 400-meter, and 3,000-meter time trials, the researchers found the group that did sprint intervals showed significant improvements in their 3,000-meter times, time to exhaustion, and small improvements in VO2 max, while the distance training group only showed slight improvements in their 400-meter times.
While interval workouts provide big-time benefits, that doesn’t mean every workout should involve intervals, Norris explains—easy runs and rest days Warm up with 10-20 min easy running.
CA Notice at Collection
Long interval workouts typically include efforts above 600 meters with moderately-long rest periods, while short interval workouts include efforts at or below 600 meters, typically with longer rest periods, explains Danny Mackey, head coach of Brooks Beasts.
If you’re training to race a 5K or shorter distance, you might find yourself running a lot of short interval workouts, whereas if you’re training for a race longer than a 5K, like a half marathon or marathon, you’ll likely lean on long intervals.
While interval workouts have shared benefits no matter the distance or duration, there are some key differences.
What Short Intervals Look Like and The Adaptations You Gain
Published: May 07, 2025 9:50 AM EDT 400-meter repeats, explains Reggie Waller, RRCA-certified run coach and head coach of Waller Endurance Coaching in Philadelphia. For example:
- Warm up with 1-mile easy jogging, followed by dynamic stretches or marathon, you’ll likely lean on long intervals
- 4-6 x 400 meters at goal 5K pace (Or 8-12 x 400-meter intervals at slightly faster than 5K pace, if you’re a more advanced 5K runner)
- Rest for 2-3 minutes, or a time that’s equal to or slightly longer than your run time between each 400-meter interval. (For example, if you run a 400 in 2 minutes, rest for 2-3 minutes of walking or light jogging)
- Cool down with 1 mile easy jogging
You typically run short intervals at a higher intensity, close to your VO2 max, which leads to better run performance and increased speed, explains Norris. Short intervals ultimately raise your top-end speed, or your “exercise ceiling,” Norris explains, so you’re able to train harder before you fatigue. This means you can run faster, for longer efforts, Norris explains.
You achieve these benefits to performance with less time on your feet, considering short intervals match some of the benefits you get in and fitness level Marathon Workouts to Get Faster.
You’ll also typically take longer rests between short intervals due to their high intensity. Mackey explains that because you’re running faster during short intervals, it takes the body more time to recover, clear lactate, and for your heart rate to come down. By giving your body enough rest time to do this—recover and clear lactate—you’re teaching it to do that more efficiently.
What Long Intervals Look Like and The Adaptations You Gain
Long intervals, on the other hand, tend to be at a more moderately-hard pace compared to high-intensity efforts in short interval workouts. You’ll typically run these at your lactate threshold, Why You Need Both Long and Short Intervals.
or marathon, you’ll likely lean on long intervals two-mile When running intervals at:
- Warm up for 1 mile at (zone 2) easy pace
- 4 What Are the Benefits of Creatine for Runners
- 1 mile jog between each rep at (zone 2) easy pace
- Cool down for 1 mile at (zone 2) easy pace
The purpose of long intervals is to improve your body’s ability to push through accompanying fatigue, explains Norris. This helps you to maintain pace after miles at marathon pace.
When running intervals at lactate threshold pace, you also push that threshold higher—training your body to run faster for longer without accumulating so much lactate that you burn out. By improving lactate threshold, Norris explains, you tend to improve your performance in distances like the 10K, half marathon, and marathon, as it allows you to run longer before bonking.
Running threshold workouts not only helps you physiologically, but also gives you the confidence you need to hit your pace (and stick with it!) on half or full marathon race day.
Why You Need Both Long and Short Intervals
All runners benefit from mastering both long and short intervals, despite their differences. Both Norris and Mackey explain that doing short and long intervals add variability to a training plan, and allow you to gain a range of adaptations like the improved lactate clearance you get from the longer intervals, and the improved muscle fiber recruitment and aerobic capacity that you gain from shorter ones.
On top of this, combining short and long intervals in a single workout often allows you to get more work in at a high intensity with less fatigue, says Norris.
For a 5K runner, a mixed workout might look like this, depending on a runner’s experience:
- Warm up with 10-20 min easy running
- 2-3 x 1K at 10K pace, 400m recovery jog in between
- 4-6 x 200m faster (3K-5K effort), 200m jog in between
- Cool down for 5-15 minutes with easy running
It’s important to keep in mind that if you’re running a shorter race, like a 5K or a 10K, feel free to incorporate mixed intervals into your training plan, but avoid doing them 10 days out from race day so you have time to recover. If you’re running a half or full marathon, hold off on doing them four to six weeks before race day, Norris says, as you’ll likely prioritize race pace as you get closer to your event.
While intervals aren’t as crucial as tempo runs for marathoners, it’s still important to be able to complete short intervals and speedwork, Mackey notes.
Norris offers an example of mixed intervals for half marathoners and marathoners:
- Warm up with 1-2 miles at easy pace
- 2 miles at marathon pace
- 3-minute jogging recovery
- 4 x 2-mile repeats at goal marathon pace
- 3-minute jogging recovery
- Run/Walk a Race
Overall, it pays to vary your intervals to become a more well-rounded runner, no matter your race distance. “By adding both to your training, you make sure you do not neglect any aspect of fitness,” says Norris. If you did only short intervals, you might struggle with holding longer efforts at half marathon or marathon pace, but if you only did those longer intervals, you may miss out on improvements to your running economy and VO2max that short intervals bring, she explains.
Associate Health & Fitness Editor Runner’s World and Bicycling in July 2024. She previously coached high school girls cross country and currently competes in seasonal races, with more than six years of distance training and an affinity for weightlifting. You can find her wearing purple, baking cupcakes, and visiting her local farmers market.
