Unlock Your Speed: How to Run a Sub-3 Hour Marathon - Lee Grantham

Aug 13, 2025

Intro: This is a quick summary of Unlock Your Speed: How to Run a Sub‑3 Hour Marathon 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

Consistency is king – aim for 12‑13 weeks of steady, quality sessions rather than a few hard days.
Interval training: run faster than marathon pace (about 10 % quicker) to teach the body efficiency at speed.
Progressive long runs: finish fast, ending at your goal marathon pace to build mental resilience and a negative‑split habit.
Strength & recovery: two strength sessions per week (glutes, hamstrings, calves, core) and prioritize sleep, nutrition, and easy runs for adaptation.

Workout Example (all paces are minutes per kilometre, distances in kilometres):

Kilometre repeats – 12 × 1 km at marathon pace 4:15 km + 10 % (≈ 3:45 km) with 60 s easy jog between each. Warm‑up 10‑15 min, cool‑down 5‑10 min.
Mile (1.6 km) reps – 8 × 1.6 km at 3:45 km, 60 s recovery. Keep the same warm‑up/cool‑down routine.
Two‑mile repeats – 4 × 3.2 km at 3:45 km, 60 s recovery. Build up the number of repeats as you get stronger.
Progressive long run – 24 km total:
- First 8 km @ 5:05 km (≈ 10 % slower than goal)
- Middle 8 km @ 4:40 km (≈ 10 % slower than goal)
- Final 8 km @ 4:15 km (goal marathon pace) Include a 7‑minute pre‑run warm‑up (slow jog + glute activation) and a cool‑down.

Practical Tips

Keep recovery intervals exactly 60 seconds to train rapid heart‑rate drops.
Warm‑up with a short 7‑minute jog focusing on glutes, calves, and hamstrings.
Add two strength sessions weekly targeting glutes, hamstrings, quads, and core to improve stride power and recovery.
Track your paces in the Pacing app and adjust the “+10 %” speeds to match your current marathon‑pace.

Closing Note: Give these sessions a try this week, and feel free to customize the distances and paces to suit your current fitness using the Pacing app. Consistent effort will get you closer to that sub‑3‑hour marathon – good luck and happy running!