Threshold Brick: 30-Minute Turbo into 20-Minute Threshold Run

Session Overview

This compact 60-minute brick session pairs a 30-minute sweet spot turbo ride with a 20-minute threshold run, training your body to deliver quality effort across both disciplines with minimal recovery. It’s an efficient midweek session for intermediate triathletes who want to sharpen their bike-to-run transition without a three-hour block.

What You’ll Need

• Turbo trainer or smart trainer
• Running shoes laid out and ready at the trainer
• GPS watch for the run split
• Fan and water on the bike

Warm-Up (10 minutes)

10 minutes easy spinning on the turbo at 90–95rpm, gradually building from Zone 1 to Zone 2. Include 3×20-second leg speed bursts at 110rpm to warm up the neuromuscular system. Stay in the saddle and keep effort relaxed.

Main Set

Bike and run performed back-to-back with the fastest possible T2 transition between them:

• Bike (30 minutes): Ride at sweet spot (88–93% FTP / Zone 3–4). Aim for consistent power throughout. Final 5 minutes, lift cadence to 95–100rpm in preparation for the run.
• T2 transition: Swap shoes as fast as possible — aim for under 60 seconds
• Run (20 minutes): First 5 minutes easy — let your legs adjust. Then 15 minutes at threshold pace (Zone 4 / RPE 7–8). Focus on keeping your upper body relaxed even as your quads protest.

Cool-Down (5 minutes)

Walk or jog very easy for 5 minutes after the threshold run effort. Then stretch your hip flexors, glutes, and calves — the three areas that take the most stress in bike-to-run transitions.

Coaching Notes

• Don’t sprint out of T2 — the first 5 minutes of the run is adaptation time, not racing time
• If your legs feel like bricks for more than 8 minutes into the run, reduce your bike effort next time by 3–5% FTP
• To progress: extend the run block by 5 minutes each week, keeping the 15 minutes at threshold constant and adding to the easy section
• Target RPE: bike = 7/10 throughout; run minutes 1–5 = 5/10, minutes 6–20 = 7–8/10