How to Build Endurance with Easy Runs
Train Smarter, Not Harder (Literally)
First, what is Endurance?
Endurance is the ability to keep going without rest or respite, mile after mile and hour after hour. Endurance doesn’t imply a specific speed or pace — that’s a topic for another video. Endurance, for the purpose of this article, is just how long or how far you can keep running.
How do you build endurance?
On a physiological level, we build endurance by pushing our muscles (including our hearts) to keep going at a steady rate even when they’re tired — or glycogen-depleted, if you want to use fancy terms. Running like this is primarily an aerobic activity, although it may take time for your legs to build up endurance as well. So the main goal is to build up your ability to keep breathing steadily for a long time, despite exertion.
You do this by, well…doing it. Remember — you’re not trying to get out of breathe, and you’re not pushing yourself to exhaustion. Those things aren’t endurance.
If you want to be able to chug along for an hour or more, you have to practice doing exactly that. So you run slowly — faster than a walk, but not so fast that you risk burning out.
You’re aiming for a pace where your breathing is slightly elevated, but steady, and your legs feel like they can keep going for a long time.
Training like this can be a double-edged sword.
On the one hand, you have to push your body far enough to stimulate an adaptive response — that is, you have to work hard enough to force your muscles and other bodily systems to become stronger or more efficient for the next time you do something this dumb.
On the other hand, if you push yourself too far you risk overreaching, resulting in an extended recovery time that limits your training, or worst-case an injury.
How do I know if my run is easy?
An easy run is exactly that — a run that feels easy. Your pacing and breathing should be comfortable (as comfortable as exercise gets), and when they stop being comfortable, you probably need to stop running or risk getting away from the goal of the run.
The great thing about easy runs is that what you consider easy will change over time, so eventually you’ll be running longer and faster than what you consider easy right now. This is progressive training.
Some people want more than just the word easy — they want to know what easy means, which I think is a weird question, but I’ll try to answer it. If you insist on using a heart rate monitor, this is probably a Zone 1 effort, or about 60–65% of your max heart rate.
But I don’t like heart rate monitors, because your heart rate varies significantly over time due to stress, sleep, nutrition, weather, and your own training. So you have to calibrate frequently, and even then, what is the monitor telling you that you don’t already know?
Eventually you’ll be running longer and faster than what you consider easy right now.
Personally, I prefer to just use the Talk Test — it’s free, just as accurate, and more fun. To check if your run is easy enough, ask yourself out loud: “Can I speak in complete sentences without gasping or pausing right now?” If the answer is yes, the run is easy enough. If you have trouble getting the question out, slow down!
How long should I run?
I prefer to measure easy runs by time, since how far you can run in a given block of time really depends on what your “easy pace” is.
Beginner athletes should start out very easy and work up slowly — getting injured or burned out is a real risk, and has caused more than one person to give up on running entirely. Don’t rush it, and don’t compare yourself to people who have been running longer — heck, don’t compare yourself to anyone!
For Beginners: When you first start out, I suggest making your goal to complete an easy run of between 10 and 20 minutes without stopping. Remember — go slow! You’re not trying to set a speed record, just build up your ability to keep moving.
Add on another 10 minutes every 3–4 weeks until you can go for an hour without stopping — now you’re not a beginner any more!
For trained athletes or experienced runners, the rules are very different — in fact, the more concerning question becomes: is there such a thing as running too long?
The answer is definitely yes.
For Experienced Athletes: Trained athletes should be running for at least 30 minutes to get any adaptive response out of an easy run, because it takes time to deplete those glycogen stores and fatigue your muscles. Better trained athletes will need to go longer or speed up to continue to benefit — again, do this incrementally every 3–4 weeks so you have time to adapt.
However, you also have to deal with diminishing returns. Exercise strengthens and improves our body by first damaging it, and then allowing it to heal and recover so that we come back stronger. It is possible to do so much damage that it takes an unreasonable amount of time to recover (say, more than 2 days) or that you increase your risk of injury to an unacceptable level.
According to Dr Shawn Bearden at Science of Ultra, a running coach, Bioenergetics research scientist, and host of the best running science podcast I’ve ever heard, the point at which these diminishing returns stop being worth it even for experienced runners is around 3 hours.
So if the goal of your easy run is to build endurance, I wouldn’t go any longer than that. If you find yourself running up against that time regularly, well…
A. Kudos to you.
B. It’s time to increase your pace and focus on getting more miles into those hours. Maybe move on to more focused training, like mountain running or speed training?
Should I ever run longer than 3 hours?
Well, sure, but not for the purposes of endurance building. If you’re running some crazy long race, you might need to go longer than that to test out your gear or your nutrition and hydration planning, or even just to build up your mental game, but make sure you also plan sufficient rest before and after.
For more on this, check out Dr. Shawn Bearden’s article, The Long Run , which is packed with awesome science and a handy graph. Honestly, reading anything on his site is worth your time.
I also wouldn’t do this any time near your actual event — probably between 4 and 8 weeks prior at the nearest.
What else should I know?
The last thing you need to know here is that you can’t just go out once a week on an easy run and expect to see much progress. Consistency is way more important than fitting in any amount of running into a single session.
To put it bluntly, running 30 minutes a day for 6 days each week will do way more for you than running for 3 hours on a Saturday afternoon and lounging around the rest of the week.
While it’s important to always plan at least one rest day every week (or two if you’re new to running, or just need extra time to recover), don’t let that become an excuse not to run. Get out there, take it easy, and remember to smile once in a while!
