3×30-Minute Ironman Race Pace Turbo Blocks

Session Overview

This 2-hour turbo trainer session builds the specific aerobic engine needed for an Ironman bike leg. Three sustained 30-minute blocks at Ironman race pace (75–80% FTP) develop fat-burning efficiency and the mental resilience to hold steady power for five-plus hours. Advanced athletes training for full or 70.3 distance will find this a cornerstone session.

What You’ll Need

• Smart turbo trainer (Wahoo KICKR, Tacx NEO, Elite)
• Power meter or reliable wattage display
• Knowledge of your FTP (20-minute test or ramp test)
• Two bidons of water + electrolyte drink
• Fan — essential for 2-hour indoor sessions

Warm-Up (15 minutes)

Ride 10 minutes at easy Zone 2 effort (55–65% FTP), then build over 5 minutes through Zone 3. Finish with 3 x 30-second accelerations to 90% FTP with 30 seconds easy recovery between each. Your legs should feel awake but your breathing should still be controlled before Block 1 begins.

Main Set

Three 30-minute blocks at Ironman race power (75–80% FTP), separated by 5-minute easy spinning recovery at 50–55% FTP. The goal is to match splits between blocks — don’t go out too hard on Block 1.

• Block 1 (30 min): 75–78% FTP. Comfortable, controlled effort. Focus on a smooth, repeatable pedal stroke at 85–90 RPM. Rest 5 minutes easy spin.
• Block 2 (30 min): 76–80% FTP. Effort feels moderate — you should be able to speak in short sentences. Drink 150–200ml per 15 minutes. Rest 5 minutes easy spin.
• Block 3 (30 min): 77–80% FTP. Hold the same power as Blocks 1 and 2 despite rising fatigue. Final 5 minutes: pick up to 82–85% FTP if you have reserves.

Cool-Down (10 minutes)

Spin at 50–55% FTP for 10 minutes, reducing cadence gradually. Don’t stop abruptly after long steady efforts — allow heart rate to return below 120 BPM before dismounting. Stretch hip flexors and hamstrings immediately after.

Coaching Notes

• Ironman race power for most athletes falls between 70–80% FTP. Know your number before starting.
• If you struggle to hold the power in Block 3, drop to 72–75% FTP on the next session and build up over weeks.
• Nutrition during the session mirrors race day — eat a small bar or gel at the 30-minute mark and again at 60 minutes.
• RPE for each block should be 6–7/10. If it feels easier, nudge power up by 5 watts; if harder, back off slightly.
• Increase the blocks to 3 x 40 minutes once this session feels manageable over three consecutive weeks.