CO2 Tolerance Assessment

Measure your Body Oxygen Level Test (BOLT) score to understand your breathing efficiency

What is CO2 Tolerance?

CO2 tolerance is an indicator of breathing efficiency and how well your body responds to carbon dioxide. Better tolerance typically means more efficient breathing patterns, better oxygen utilization, and improved stress resilience.

What is the BOLT Score?

The BOLT (Body Oxygen Level Test) score measures in seconds the comfortable breath-hold time after a normal exhalation. It reflects your body's "air hunger" threshold and sensitivity to CO2 buildup.

Important Safety Information

This is NOT a medical diagnostic tool. It is for educational and wellness purposes only.

Do NOT perform this test if you:

  • Have cardiovascular or respiratory conditions
  • Are pregnant
  • Have recently experienced panic attacks
  • Are feeling unwell or dizzy

Stop immediately if you experience:

  • Intense discomfort or pain
  • Dizziness or lightheadedness
  • Panic or severe anxiety

Ideal Testing Conditions

  • •Be at rest and seated upright in a quiet environment
  • •Avoid testing after exercise or meals (wait 2-3 hours)
  • •Do not test during or after stressful activities
  • •Best performed in the morning after waking

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