MUD WORKOUT Marine Corps Lance Cpl. Matthew Ross performs full-body exercises in the mud during physical training as part of the Advanced Machine Gunner Course on Camp Geiger, N.C., April 20, 2015. Ross is a machine gunner and student with the Advanced Infantry Training Battalion. SHARE IMAGE: Download Image: Full Size (0.07 MB) Photo By: VIRIN: 555271-P-PUQ50-570.jpg Photo Gallery