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Methods Inf Med 1997; 36(04/05): 368-371
DOI: 10.1055/s-0038-1636856
DOI: 10.1055/s-0038-1636856
Original Article
Continuous Estimation of CO2 Production during Exercise
Further Information
Publication History
Publication Date:
19 February 2018 (online)
Abstract.
A new method was developed for continuous isotopic estimation of human whole body CO2 rate of appearance (Ra) during non-steady state exercise. The technique consisted of a breath-by-breath measurement of 13CO2 enrichment (E) and a real-time fuzzy logic feedback system which controlled NaH13CO3 infusion rate to achieve an isotopic steady state. Ra was estimated from the isotope infusion rate and body 13CO2 enrichment which was equal to E at the isotopic steady state. During a non-steady state incremental cycle exercise (5 w/min or 10 w/min), NaH13CO3 infusion rate was successfully increased by the action of feedback controller so as to keep E constant.
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