Broken-Mile Speed Builder

Workout - Broken-Mile Speed Builder

• 12min @ 6'15''/km
• 2 lots of:
  • 1.6km @ 5'00''/km
  • 2min rest
  • 400m @ 4'45''/km
  • 1min rest
  • 400m @ 4'45''/km
  • 1min rest
  • 400m @ 4'45''/km
  • 1min rest
  • 400m @ 4'45''/km
  • 1min rest
• 10min @ 6'15''/km

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Intro

Here’s a breakdown of “This Workout Helped Me Get From 2 hrs 10 mins to 1 hr 45 mins For A Half Marathon” from The Running Channel—it’s definitely worth watching in full. We’ve distilled the essentials so you can take it out for a run this week. The video has more context around technique and pacing strategy, so check it out if you want the complete picture.

Key Points

• The broken-mile workout pairs a sustained 1-mile push at 10K pace (~5 min/km) with shorter 400m bursts near 5K effort. You get endurance from the long segment and speed work from the sprints.
• Target 5 min/km for the mile and around 4:45/km on the 400m repeats (roughly 5K effort).
• Walk for 2 minutes after the mile, then 60 seconds between each 400m.
• This structure fits well into taper phases, early halves, or the weeks just before a race when you want to sharpen up.
• Run alongside someone faster if you can—having a training partner on the short repeats helps you stick to the target pace.

Workout Example

Warm-up: 5–10 minutes of easy running, plus drills and dynamic stretches.

Set 1

1. 1 mile (1.6 km) at 5 min/km (your 10K pace). Follow with a 2-minute walk.
2. 4 × 400 m at ~4:45/km (or roughly 55 sec/400m), with 60 seconds of walking rest between each.
3. Run Set 1 again (the mile and four 400s).
4. Cool-down: 5–10 minutes at an easy pace.

Tips

• Set lap markers on your watch for each 400m segment—makes pacing feedback immediate.
• Keep the opening mile controlled; this isn’t a sprint.
• On the 400s, hit your target from the gun; don’t let yourself drift fast early and fade.
• Stay sharp with your mechanics: shoulders back, breathe deep, drive your knees and arms.
• Use this as practice for the mental side of racing—holding a quick pace when your legs are tired is what separates strong finishes from faded ones.

Closing Note

Take this session for a spin and dial the paces to your own zones using the Pacing app. It’s a workout that builds confidence and teaches your body that half-marathon pace is within reach. Get after it.

References

• This Workout Helped Me Get From 2 hrs 10 mins to 1 hr 45 mins For A Half Marathon - YouTube (YouTube Video)