I Ran A 66 Minute Half Marathon After THIS WORKOUT - Ben Is Running

Aug 13, 2025

Intro: This is a quick summary of “I Ran A 66 Minute Half Marathon After THIS WORKOUT” from Ben Is Running. It’s a great watch — we’re breaking it down so you can try the workout today. Be sure to check out the full video for all the details.

Key Points:

The workout is a 7 × 2 km intervals (half‑marathon intensity) each followed by a 1 km easy float (total ~22 km with a 3 km warm‑up).
At altitude you should slow your pace by about 10‑12 seconds per km compared to sea‑level effort.
Target pace for the 2 km “on” intervals: ~3:25 min/km (≈ half‑marathon effort) and for the 1 km “float” about 4 minutes (≈ 3:50‑3:55 min/km).
Heart‑rate stays high (around 160 bpm) during floats at altitude – a good reminder to monitor effort and stay fresh.
The runner stopped after 6 reps (instead of 7) to avoid over‑reaching before the race, showing the importance of tapering and listening to your body.

Workout Example:

Warm‑up: 3 km easy (out‑and‑back)

Repeat 6‑7 times:
  • 2 km at ~3:25 min/km (half‑marathon intensity)
  • 1 km easy float at ~3:50‑3:55 min/km (≈4 min) – keep HR around 160 bpm

Total volume: ~22 km (including warm‑up)

If you’re training at sea level, aim for ~3:10 min/km on the 2 km intervals (the altitude pace translates to roughly 3:10 min/km at sea level.)

Practical Tips:

Adjust for altitude – add ~10‑12 seconds per km to your usual paces.
Monitor heart‑rate during floats; if it stays high, consider a slightly slower float or a shorter interval.
Taper wisely – cut the session short (6 reps) to stay fresh for race day.

Closing Note: Give this altitude‑adjusted 2K‑1K float workout a try and tweak the paces to match your own recent training in the Pacing app. Good luck, and enjoy the boost it gives you for a fast half‑marathon! 🚀