Tactical Fitness Class
U.S. Marine Maj. Macro Serna, U.S. Strategic Command, holds a piece of polyvinyl chloride pipe while U.S. Air Force Staff Sgt. Bryan Holm, 338th Combat Training Squadron, demonstrates how to do a shoulder press during the tactical fitness class in the field house on Offutt Air Force Base, Neb., Nov. 3. Serna is a CrossFit Level 1 certified instructor.
(U.S. Air Force photo by Charles Haymond/Released)