Mastering the Long Run: How Long Should Your Long Run Be? - Lee Grantham

Aug 13, 2025

Intro

This is a quick summary of Mastering the Long Run: How Long Should Your Long Run Be? 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

Start small: If you’re running 5‑6 km (≈35‑40 min) three‑four times a week, begin your long run at about 40‑45 minutes (roughly a 10 % increase over your usual run).
Progress gradually: Add 5‑10 minutes to your long run every week for three weeks, then cut back on the fourth week to let your body recover.
Long‑run cadence: Aim for zone‑2 (conversational) pace, ideally matching the pace you plan for your target race (e.g., 6 min/km for a 2 h 8 min half‑marathon).
Weekly progression pattern:
- Week 1: 10 km (or 40 min)
- Week 2: 11 km
- Week 3: 12 km
- Week 4: back‑off to 10 km
- Repeat with a slight increase (14 km, 15 km, etc.)
Long‑run mileage ladder: 30 km → 32 km → 35 km → cut back to 25 km on the 4th week, then build to 38‑40 km later in the cycle.
Mental & nutrition prep: Use long runs to train your stomach and metabolism (carb intake) so race‑day nutrition feels familiar.

Workout Example

Week 1: 40‑45 min easy run (zone‑2)
Week 2: +5 min (≈50 min) – keep same pace
Week 3: +5 min (≈55 min) – keep same pace
Week 4: Cut back to 40 min (recovery week)

Repeat cycle, gradually increasing the total time by ~5 % each week.

Long‑run distance progression (example in km):
- 10 k → 11 k → 12 k → 13 k → **back‑off** to 10 k → 14 k → 15 k → …

Or for higher mileage runners:
- 30 k → 32 k → 35 k → **25 k** (recovery) → 38 k → 40 k

Closing Note

Give this progressive long‑run plan a try and tweak the times to match your own paces in the Pacing app. Consistency and smart cut‑back weeks will keep you strong, injury‑free, and ready for your next race. Good luck, and enjoy the journey!