SmO₂ (muscle oxygen saturation) describes the balance between the oxygen delivered to the muscle and the oxygen it consumes during exercise. This parameter changes in real time as exercise intensity changes.
What happens to muscle oxygenation during exercise?
The harder a muscle works, the more oxygen it needs. Your body responds by increasing the flow of oxygen-rich blood. If the muscle's oxygen demand exceeds the body's ability to supply it, muscle oxygenation (SmO₂) decreases, while lactate levels may begin to rise.
How does QLAC measure it?
QLAC uses NIRS (Near-Infrared Spectroscopy) technology. An LED emits near-infrared light, and detectors positioned at two different distances analyze hemoglobin signals from both superficial and deeper layers of muscle tissue.
- The 1,5 cm channel analyzes the superficial layer of the tissue.
- The 3 cm channel allows you to monitor changes occurring in deeper tissue layers.
- Data is collected eight times per second.
This allows the app to display real-time changes in muscle oxygenation during exercise.
Key takeaways
A single value does not provide the full picture. The most useful information comes from the SmO₂ trend viewed together with exercise intensity, training zone, and the conditions in which the measurement was taken.
