How to Run a Sub-3 Hour Marathon (Step-by-Step Training Plan) - Lee Grantham

Aug 13, 2025

Intro This is a quick summary of How to Run a Sub‑3 Hour Marathon (Step‑by‑Step Training Plan) 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

Target marathon pace: 4:15 /km (≈ 6:52 /mi) – the goal is to make that pace feel easy by getting faster at shorter distances.
The plan consists of six core interval sessions, each with two progressive paces (marathon pace, then faster at 4:00 /km and 3:45 /km).
Progression is based on feeling strong at the end of each session; move to the faster pace when you can finish the reps with effort left.
Warm‑up is crucial: light jog, check for soreness, then build up to the target effort before the first reps.
Consistency across weeks builds speed, strength, and marathon‑specific fitness while also improving 10 k and half‑marathon PBs.

Workout Example (Session 1 – “ABC”):

Total distance: 6 km total, broken into 12 × 500 m repeats.
Rest: 60 seconds between each repeat.
Pace 1 (Marathon pace): 4:15 /km (6:52 /mi).
Progression 1: Same 12 × 500 m at 4:00 /km (≈ 6:26 /mi).
Progression 2: Same 12 × 500 m at 3:45 /km (≈ 6:04 /mi).
When to progress: If you finish the 12 reps feeling you could do 2‑3 more reps, move to the next faster progression.

The other five sessions follow the same pattern but increase the interval length:

Session 2: 10 × 600 m (same rest) at 4:15 → 4:00 → 3:45 km.
Session 3: 8 × 800 m at the same paces.
Session 4: 6 × 1 km.
Session 5: 4 × 1.5 km.
Session 6: 3 × 2 km.

Each session starts at marathon pace, then progresses to 4:00 /km and finally 3:45 /km as you become comfortable. Adjust the paces to match your own marathon goal using the Pacing app.

Closing Note Give this structured interval plan a try, tweak the paces to fit your current fitness, and watch your marathon pace become easier. Customize the workout in the Pacing app and keep building toward that sub‑3 hour goal. Good luck, and enjoy the journey! 🚀