WILBERT S. ARONOW, M.D., F.A.C.P.; JOHN CASSIDY, M.D.
The effect of breathing 100 ppm of carbon monoxide versus compressed, purified air for 1 h on maximal treadmill exercise was studied (double-blind crossover design) in 10 middle-aged, healthy nonsmokers. The mean venous carboxyhemoglobin level significantly increased from 1.67% to 3.95% after breathing carbon monoxide (P < 0.001) and significantly decreased from 1.63% to 1.30% after breathing compressed, purified air (P < 0.001). The mean exercise time until exhaustion significantly decreased from 697.7 s to 662.7 s after breathing carbon monoxide (P < 0.001) and insignificantly increased from 694.9 s to 703.4 s after breathing compressed, purified air. Ischemic S-T segment depression ≥ 1.0 mm after exercise occurred in 1 of 10 subjects after exercise following carbon monoxide inhalation. Increased carboxyhemoglobin levels of the magnitude encountered after smoking or heavy atmospheric pollution impair exercise performance in normal persons.
ARONOW WS, CASSIDY J. Effect of Carbon Monoxide on Maximal Treadmill Exercise: A Study in Normal Persons. Ann Intern Med. ;83:496–499. doi: 10.7326/0003-4819-83-4-496
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Published: Ann Intern Med. 1975;83(4):496-499.
Cardiology, Coronary Risk Factors, Emergency Medicine, Hospital Medicine, Smoking.
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Print ISSN: 0003-4819 | Online ISSN: 1539-3704
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