3 KEY sessions to help improve your THRESHOLD running speed - Stephen Scullion - Olympic marathoner

Aug 13, 2025

Intro: This is a quick summary of 3 KEY sessions to help improve your THRESHOLD running speed from Stephen Scullion – Olympic marathoner. It’s a great watch, and 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:

Running the same threshold session week after week limits adaptation; mixing up the format keeps the body responding positively.
Stephen outlines three effective threshold styles: (1) short threshold intervals (2‑3 km repeats), (2) sustained tempo runs (20‑45 min), and (3) progressive runs that start easy and gradually speed up.
Keep an eye on heart‑rate lag – it can take 7‑10 min for HR to settle into the true threshold zone, so start conservatively and let the effort rise.
Use recovery jogs or short rests in interval work to pull the heart rate back down and stay inside the threshold band.

Workout Example – Progressive Run:

Choose a distance you’re comfortable with (e.g., 10 mi/16 km).
Start at a pace about 20‑30 s slower than your typical threshold (e.g., 5:40 / mi or 9:00 / km).
Every 2 mi (≈3 km) or every 3‑4 min, pick the pace up a little (5:30 / mi, then 5:20 / mi, etc.) while monitoring HR to stay in the threshold zone (≈140‑170 bpm).
Finish the run at the higher end of your threshold (around 5:10 / mi).
Total time ≈ 20‑45 min of continuous effort.

Closing Note: Try one of these three threshold sessions this week, and feel free to tailor the paces in the Pacing app to match your own fitness. Adding variety will keep your body adapting and your speed climbing – go for it!