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Blow out as hard and fast as you can. You want to move the marker as far as you can with your breath, so concentrate on exhaling forcefully and quickly.
Review Date 1/1/2025
Updated by: Frank D. Brodkey, MD, FCCM, Associate Professor, Section of Pulmonary and Critical Care Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
