One-Hour Workout: Endurance Build Run

Work on your pacing—and your aerobic endurance—with this simple build run.

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Sometimes the simple workouts are the best ones—and this endurance build run is exactly that, with a gentle progression in pace and effort as you work through the session. It’s also easy to scale it back (or beef it up!) based on energy, fatigue, and time available.

Begin with a 20-minute easy, relaxed pace run, aiming for rate of perceived exertion (RPE) 5/10, progressing to a 6/10 by the end of the 20 minutes. Next, you’ll nudge the effort up to a 6-7/10 RPE for 15 minutes, being sure to build the pace through the 15 minutes. You’ll then shift gears again, this time running for 10 minutes at 7-8/10 RPE. This should be a moderately strong effort which is beginning to feel slightly uncomfortable by the end of the 10-minute block. Be sure to remain focused on your form and breathing as your effort increases. The final block of “work” is five minutes at a strong effort (think 8-9/10 RPE), which should feel like a solid/hard effort and, ideally, you’ve progressed your speed throughout. Wrap it up with a five to 10-minute cool-down.

If you want to make this workout longer and/or you’re feeling strong, then begin with a 30-minute interval and progress as: 20 minutes, 15 minutes, 10 minutes (following the same effort/intensity pattern).

Be sure to start out easy/relaxed so that you can progress effort accordingly—it’s a sign of a well-executed session if your pace has increased well with each interval. This helps fine tune your ability to pace yourself and learn the art of pacing while also building your aerobic endurance.

One-Hour Workout: Endurance Build Run


20 min. easy running @ 5-6/1o RPE

Main set:

15 min. @ 6-7/10 RPE

10 min. @ 7-8/1o RPE

5 min. @ 8-9/10 RPE


5-10 min. easy jog