JOINT BASE LANGLEY-EUSTIS, Va. – Samantha Melius, Armed Forces Wellness Center supervisory health educator, prepares David Pittman, U.S. Army Training and Doctrine Command Headquarters personnel, for the Vo2 Submax Testing at Joint Base Langley-Eustis, Virginia, Sept. 7, 2023. Melius applied a mask onto Pittman’s face to track his oxygen intake while he ran on the treadmill. (U.S. Air Force photo by Airman 1st Class Adisen Smith)