How to build running endurance over time

If you're new to running, you might be wondering how experienced runners do things like run marathons — it seems so far away. But no matter where you are in your running journey, learning how to build running endurance is a skill you'll use for many years to come. And while miles and pace will vary, truth be told, the same basic principles apply to elites as they do for beginners when it comes to building endurance.

Every runner has different goals, especially when you're just starting out. But figuring out how to build running endurance is usually at the top of most runners' lists. Keep in mind that every runner is different, and what works for one might not work for the other. However, whether you're starting at a mile and working your way up or going from running a half-marathon to a full, there are certain standard principles that can help you gradually extend your endurance.

Once you've established a base for endurance running, you can take the next step — working to get faster for a longer period of time. But first things first: Here are some overarching guidelines for building running endurance.

Don't bite off more than you can chew

The secret to building running endurance is to approach it gradually, rather than diving in. You've discovered you actually like this thing called running, right? The fastest way to end up on the injured reserve list is to run too far, too fast, too soon.

Instead, make a plan for the slow build. If you are able to run a couple of miles at a stretch and do it consistently a few times a week, try adding on an extra five to 10 minutes of running the next time out. A week later, do the same for one or two of your runs. Before you know it, 2 miles will have become 4 miles.

Once you have a couple of months of consistently running at least 3 miles or 30 minutes at a stretch, pick one run a week to focus on developing a longer run. This will be your key workout each week, and by slowly adding on a mile or so to it each week, you'll build solid endurance.

Slow as you go

A word on pacing — easy is the way to go, especially while you're building in a longer run each week. One of the most common mistakes even veteran runners make is placing too many of their miles in a speedier running zone. As hard as it is, hold back when heading out, especially while building your endurance.

Lots of good things happen when you run at a steady, easy pace. Your muscles start building more mitochondria, the "powerhouse" of a cell. More mitochondria lead to better conversion of nutrients into energy. That translates into more endurance — exactly what you're after.

To keep yourself in check, aim for getting in most of your mileage at about 80% of the speed you could race at a given distance. Say you recently ran a 10K at a 10-minute pace, for instance. If you're headed out for a 6-mile training run, slow that pace down to about a 12-minute pace.