Information
Critical Speed and Critical Power Concepts for Determining HYROX Performance
Oct 11, 2025
Understanding Critical Speed and Critical Power
Both critical speed and critical power are well-established concepts in sports science. They represent the threshold separating sustainable metabolic work from unsustainable effort. In other words, intensities below this threshold can be maintained for extended periods, while intensities above it lead to rapid fatigue and performance decline.
Mathematically, the relationship between speed (or power) and the duration or distance that can be sustained follows a hyperbolic curve. As running speed or power output increases, the duration for which that effort can be maintained decreases nonlinearly.
Application to HYROX Performance
For HYROX athletes, understanding individual CS and CP values provides two key benefits:
Optimizing Race Pacing: Knowing your CS/CP helps you set a sustainable running and erg-machine pace that balances intensity and fatigue across HYROX.
Guiding Training Prescription: These metrics can also be used to define personalized training zones, allowing you to target specific physiological adaptations in your daily sessions.
How to Determine Your Critical Speed or Power
To simplify the process, we’ve created two easy-to-use apps that allow you to estimate your CS or CP based on short field tests:
Running: Perform two all-out efforts, one lasting 3 minutes and another 12 minutes.
Ergometer: Perform two maximal efforts over 1,000 m and 5,000 m distances.
While including more data points can increase accuracy, the two-effort model provides a reliable and practical estimation for most athletes.
You can calculate your own values and training zones using the following links:
Setting the Right HYROX Pacing
Given the additional fatigue imposed by the strength stations, the Hyrox running pace can be set between 85–95% of critical speed, corresponding to Zone 5 intensity in the app. However, this should be adjusted based on your experience and conditioning level. For many athletes, the ideal Hyrox pace will fall somewhere between Zone 4 and Zone 5.
