We’re continuing our weekly workout series with another endurance workout that will help you work on establishing a good pace for longer distances and races. Short intervals will develop your speed, but if you want to improve your endurance, increase the duration of your intervals and slow them down a bit. Two-mile repeats will build your endurance, teach you how to pace yourself over longer distances, and increase your resistance to fatigue.

Two-mile threshold repeats will improve your endurance for any race distance from the 5K to the marathon. They do not replace the long run, but rather they supplement it and further build upon the endurance you gain from your weekly long run. Two-mile repeats can be done at any point in the training cycle. They are particularly valuable in the earlier weeks of marathon or half marathon training to help boost your endurance and prepare you for long tempo runs at goal race pace. For the 10K, these longer repeats will boost your endurance at any point in training, so that you don’t slow down during the final mile push of either race.

Your threshold pace is approximately your hour-long race pace. For most recreational runners, this equates to the pace of a recent 10K to 15K race.

In terms of effort, two-mile repeats should feel comfortably hard and you should be able to speak in short phrases but not carry on a conversation. During the run, you should feel as if you could sustain this effort for 30-40 minutes continuously in that run if needed. If you don’t think you can do so, slightly ease back and reassess. These intervals are not time trials, so do not run them at an all-out effort.

Ideally, this workout should be done on a flat stretch of road or gently rolling hills, as it can be difficult to maintain the appropriate pace when running on steep uphills and downhills. You can also do this on a track or paved trail.

The Workout

  • Warm-up 1-2 miles of running at a light, conversational effort.
  • Run 2 miles at your threshold pace (comfortably hard effort). Jog slowly for 2 minutes to steady your breathing and recover, then run a second set of 2 miles at your threshold pace.
  • Cool down with 1-2 miles of running at a relaxed effort.

Ready to run? Get started here!