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Updated: Jul 16, 2026
06:27
Fast and Accurate Exhaled Breath Ammonia Measurement
Published on: June 11, 2014
Exhaled breath condensate pH is increased after moderate exercise
Michael Riediker1, Brigitta Danuser
1Institute for Occupational Health Sciences, Lausanne, Switzerland. michael.riediker@alumni.ethz.ch
Summary
Moderate exercise temporarily increases exhaled breath condensate pH in healthy individuals. This finding challenges the use of exhaled breath condensate pH for diagnosing inflammatory diseases in health surveys.
Area of Science:
- Pulmonary Medicine
- Biochemistry
- Occupational Health
Background:
- Exhaled breath condensate (EBC) pH is lower in patients with inflammatory diseases.
- EBC pH may be a useful biomarker for inflammatory processes.
- The influence of physical activity on EBC pH requires investigation for its diagnostic utility.
Purpose of the Study:
- To determine if moderate exercise affects exhaled breath condensate pH.
- To assess the potential interference of physical activity with EBC pH measurements.
- To evaluate the feasibility of using EBC pH for health surveys and diagnostics.
Main Methods:
- Fifteen healthy, nonsmoking subjects performed 30 minutes of moderate treadmill exercise.
- Exhaled breath condensate (EBC) samples were collected before, immediately after, and 60 minutes post-exercise.
- pH levels of EBC samples were measured and analyzed.
Main Results:
- Exhaled breath condensate pH significantly increased immediately after exercise compared to pre-exercise levels (8.27 vs. 8.20, p = 0.001).
- The elevated EBC pH persisted for at least 60 minutes post-exercise (8.25, p = 0.02).
- The pH increase was more pronounced in individuals with initially lower EBC pH.
Conclusions:
- Moderate physical activity leads to a significant and sustained increase in exhaled breath condensate pH.
- The persistent elevation of EBC pH post-exercise poses a challenge for its use in diagnostic applications and health surveys.
- This effect could mask or interfere with the detection of decreased EBC pH associated with inflammatory conditions.
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