Respiratory ammonia output and blood ammonia concentration during incremental exercise

W. Ament*, J.R. Huizenga, E. Kort, T.W. van der Mark, R.G. Grevink, G.J. Verkerke

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

47 Citations (Scopus)


The aim of this study was to investigate whether the increase of ammonia concentration and lactate concentration in blood was accompanied by an increased expiration of ammonia during graded exercises. Eleven healthy subjects performed an incremental cycle ergometer test. Blood ammonia, blood lactate and the amount of expired ammonia were measure until 30 minutes post exercise. The expired air was guided through a flow chamber filled with a sulphuric acid solution to trap the expired ammonia. Blood ammonia, blood lactate increased more than proportionally and the amount of expired ammonia (in μmol/min) increase expotentially with the workload. Post-exercise the amount of expired ammonia decreased within a few minutes back to pre-exercise levels while the concentrations of lactate and ammonia in blood decreased much more slowly and were sill elevated after 30 minutes of recovery. We conclude that the more than proportional increase to ammonia and lactate during graded exercise, is accompanied with an exponential increase of expired ammonia output. Faster and more accurate ammonia gas detection techniques are necessary to quantify more precisely the respiratory ammonia output during graded exercise.

Original languageEnglish
Pages (from-to)71-77
Number of pages7
JournalInternational Journal of Sports Medicine
Issue number2
Publication statusPublished - 1 Jan 1999


  • Ammonia expiration
  • Blood ammonia
  • Incremental exercise

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