Key Takeaway
Six weeks of inspiratory muscle training improved 20km and 40km cycling time trial performance by 3.8% and 4.6% respectively in trained cyclists.
Summary
Landmark RCT demonstrating that specific inspiratory muscle training improves cycling time trial performance. Using a double-blind placebo-controlled design, trained cyclists showed significant improvements in both short and long time trials after 6 weeks of pressure-threshold IMT.
Methods
- Randomized double-blind placebo-controlled trial
- 16 trained male cyclists (VO2max = 64 ml/kg/min)
- 6-week intervention: IMT vs sham training
- Pressure-threshold IMT at 50% max inspiratory pressure
- 30 breaths twice daily
- 20km and 40km simulated time trials
Key Results
- 20km time trial: 3.8% faster (66 seconds improvement)
- 40km time trial: 4.6% faster (115 seconds improvement)
- Increased maximal inspiratory pressure
- Reduced perception of breathlessness
- No change in VO2max
Limitations
- Trained male cyclists only
- Laboratory-based time trials
- 6-week duration
- Placebo effect possible (participants may have guessed group)