MY FAVOURITE MARATHON SESSION: TRAINING FOR A SUB 2:25 MARATHON - The Welsh Runner

Aug 13, 2025

Intro

This is a quick summary of MY FAVOURITE MARATHON SESSION: TRAINING FOR A SUB 2:25 MARATHON from The Welsh Runner. 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 session is a kilometer‑on/kilometer‑off (alternation) workout: fast km at half‑marathon pace, recovery km just a bit slower than marathon pace.
Goal: the average pace of the whole run equals your target marathon pace (≈5:30 mi or 8:52 km).
Fast segments: ~5:10 mi (3:13 km). Recovery segments: ~5:43‑5:50 mi (3:33‑3:35 km).
Total work: about 21 km (≈13 mi) of alternations, plus a 5 km warm‑up and a cool‑down, ending up around 18‑20 mi total.
No fueling during the run; the fast bits build lactate, the slower bits clear it, mimicking marathon‑specific stress.

Workout Example

5 km easy warm‑up
Repeat the following alternation for ~21 km (≈13 mi):
- Fast km @ half‑marathon pace (~5:10 / mi or 3:13 / km)
- Recovery km @ ~5:45‑5:50 / mi (≈3:33‑3:35 / km)
Cool‑down – easy jog until you reach a total of 18‑20 mi (≈29‑32 km). Adjust the number of alternations or the total distance to match your current fitness and the paces you can hold in the Pacing app.

Closing Note

Give this session a go this week, tweak the paces to fit your own marathon goal, and watch the splits in the Pacing app. You’ll boost confidence, sharpen your marathon‑specific stamina, and be ready for race day. Happy running!