As cyclists, we’ve all experienced that lung-burning sensation when climbing steep hills. Now imagine that feeling amplified – that’s what happens when you ride at higher elevations. At altitudes above 5,000 feet (1,500 meters), the air pressure decreases, resulting in less oxygen available in each breath you take.
Understanding the Science Behind Altitude and Cycling
For your muscles to function optimally during cycling, they need a constant supply of oxygen. When this supply diminishes at higher elevations, several physiological changes occur: your blood carries less oxygen to working muscles, your breathing rate increases as your body tries to compensate, your heart works harder to deliver oxygen throughout your body, and your maximum oxygen consumption capacity decreases by roughly 1-2% for every 1,000 feet of elevation gain.
How Altitude Affects Your Ride
The effects of altitude on your cycling performance are quite noticeable, particularly if you’re not acclimatised. Most cyclists experience a 7-10% decrease in sustainable power at elevations around 6,500 feet. Recovery between intervals or climbs takes longer, perceived exertion increases, making comfortable sea-level paces significantly more challenging, and dehydration risk rises as higher altitudes typically have lower humidity and can accelerate fluid loss.
Before Your High-Altitude Ride
Give yourself 3-7 days to acclimatise before attempting challenging routes if possible. Start hydrating days before your ride and continue throughout. Your body may require more carbohydrates at altitude, so adjust your nutrition accordingly. Most importantly, set realistic expectations by revising your time and power goals to match the conditions.
During Your High-Altitude Ride
Start at 70-80% of your normal effort level and adjust based on how you feel. Expect your heart rate to be 10-15 beats higher than normal for the same perceived effort. Focus on full, deep breaths rather than shallow panting, and aim for an extra 16-24 oz of fluid per hour compared to lower elevations to stay properly hydrated.
Equipment Considerations for High-Altitude Riding
Your gear choices can make a significant difference when tackling high-elevation routes. Consider a cassette with a larger range (e.g., 11-34T or greater) to help on climbs. Slightly lower tyre pressures can provide better traction on loose mountain terrain. Since UV exposure increases approximately 4-5% for every 1,000 feet of elevation gain, appropriate sun protection is essential. Temperature fluctuations are more extreme at altitude, so dress in versatile layers.
The Long-Term Benefits
While the immediate impact of altitude on cycling performance is challenging, there are potential benefits to training at elevation. Your body adapts by producing more oxygen-carrying red blood cells, and your muscles become more efficient at extracting available oxygen. Overcoming the difficulties of high-altitude riding builds mental toughness, and many cyclists report feeling stronger when returning to sea level after altitude training.
Conclusion
Altitude presents unique challenges for cyclists, but with proper preparation, appropriate pacing, and the right mindset, high-elevation rides can be incredibly rewarding experiences. The stunning vistas and sense of accomplishment that come with conquering mountain passes make the extra effort worthwhile.
Written by Niall O’Riordan UBS