How to Know Your Real Marathon Pace (Not Just Guess It) - Lee Grantham

Aug 13, 2025

Intro: This is a quick summary of How to Know Your Real Marathon Pace (Not Just Guess It) from Lee Grantham. 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:

Your marathon pace must come from the training you’ve already done, not just the time you want to hit.
Use long runs, marathon‑pace blocks, and interval sessions to reveal the pace you can sustain for 42 km (26 mi).
Start where you are now and gradually nudge the marathon‑pace segment faster each week (e.g., from 4:30 km to 4:15 km).
Include recovery/easy runs, mid‑week faster intervals, and a 10‑day taper to keep legs fresh.

Workout example:

Marathon‑pace block (25 km total): 5 km easy, 15 km at current marathon pace, 5 km easy. Begin with a pace of ~4:30 min/km (≈6:52 min/mi) and trim 5‑10 seconds each week toward 4:15 min/km (≈6:52 min/mi).
5×10‑minute intervals: Warm‑up, then 5 repeats of 10 min at ~5 % faster than marathon pace with 60 sec jog recovery. Great for testing if you can hold a faster pace (e.g., 4:00 min/km for a 2:52 marathon).
Progression run (24 km / 15 mi): 8 km easy, 8 km at marathon pace, 8 km easy. Adjust the middle segment to your target pace (4:15 min/km or 6:52 min/mi).
Half‑marathon marathon‑pace rehearsal: 4 km easy, then 4 km at marathon pace + 20 % (slightly faster), followed by the remaining 12 km at true marathon pace. This builds confidence for the 32 km mark in a race.

Practical tips you can use now:

Run a 25 km long run with a 15 km marathon‑pace chunk to gauge comfort.
Schedule a weekly interval session that’s a bit faster than marathon pace to improve speed endurance.
Taper for 10 days before race day to let legs recover while keeping the “zip” in them.

Closing note: Try one of these runs this week, adjust the paces to match your current fitness, and watch your confidence grow. You can always customize the distances and paces in the Pacing app to fit your own goals. Happy training, and may your next marathon be faster than you imagined!