Turbo Trainer Intervals: FTP Builder

Session Overview

This 60-minute turbo trainer session is designed to build your Functional Threshold Power (FTP) through sustained efforts just below threshold. It’s ideal for intermediate cyclists preparing for race season who want to improve their ability to hold high power outputs.

What You’ll Need

  • Turbo trainer or smart trainer
  • Power meter or heart rate monitor
  • Water bottles (at least two)
  • Fan for cooling
  • Towel

Warm-Up (15 minutes)

Start with 10 minutes of easy spinning at 50-60% FTP (Zone 1-2), gradually increasing cadence to 90rpm. Follow with three 30-second bursts at 90% FTP with 90 seconds easy recovery between each. Finish with 3 minutes at 65% FTP to stabilise your heart rate.

Main Set

The main set consists of three blocks of sustained efforts at 88-93% FTP (sweet spot training zone). This intensity builds the muscular endurance needed to hold threshold power for longer periods.

  • Block 1: 10 minutes at 88-93% FTP, 5 minutes easy recovery (50% FTP)
  • Block 2: 10 minutes at 88-93% FTP, 5 minutes easy recovery (50% FTP)
  • Block 3: 8 minutes at 90-95% FTP, targeting the upper end of sweet spot

During each interval, maintain a steady cadence between 85-95rpm. Focus on smooth pedal strokes and controlled breathing. The efforts should feel challenging but sustainable—you should be able to speak in short sentences.

Cool-Down (7 minutes)

Spin easy at 40-50% FTP for 7 minutes, gradually reducing intensity. Focus on keeping your legs moving to flush out lactate. Drop your cadence to 80rpm for the final 2 minutes.

Coaching Notes

  • RPE guidance: Main intervals should feel 7-8/10 effort. If you’re struggling to complete the intervals, reduce intensity by 3-5%.
  • Cadence focus: Resist the urge to grind at low cadence. Higher cadence (85-95rpm) is more sustainable and builds better pedalling efficiency.
  • Hydration: Drink 200-300ml every 15 minutes. Indoor training causes more fluid loss than outdoor riding.
  • Progression: Once you can complete all three blocks comfortably, increase the third block to 10 minutes or add a fourth 6-minute block.
  • Recovery: This is a challenging session. Schedule an easy day or rest day afterwards.

Training at your own risk. The information provided is for general guidance only and is not a substitute for professional medical advice. Please consult a doctor before starting any new exercise programme, especially if you have any pre-existing health conditions.