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Updated: Jun 6, 2026

Dual Test Gas Pulmonary Diffusing Capacity Measurement During Exercise in Humans Using the Single-Breath Method
Published on: February 2, 2024
Prevalence and characteristics of lung function changes in recreational scuba divers
1School of Nursing, The University of Adelaide, Adelaide, South Australia, Australia. anne.wilson@adelaide.edu.au
Aims:
To investigate the hypothesis that a salt water SCUBA dive may cause bronchoconstriction in some individuals.
Methods:
100 experienced recreational SCUBA divers acted as their own controls. Spirometry measures were taken with Easyone(TM) spirometers before and after a dive. Measures recorded included FEV1/FVC ratio and forced mid-expiratory flow (FEF25-75%).
Results:
60 participants (68% male, 32% female) aged between 19-68 years (mean 47 years) produced data meeting ATS/ERS international standards. Of these, 23% exhibited pre-dive FEV1/FVC ratio values less than 75%. Statistics on paired samples of pre- and post-parameters showed a significant decrease in FVC post-dive but did not show significant reductions in FEV1 or FEV1/FVC. Six (10%) were current smokers and 13 (21%) were former smokers.
Conclusions:
25% of participants had reduced FEV1/FVC ratio regardless of undertaking a dive. Consideration of the clinical implications requires further investigation.
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