Retired U.S. Air Force Maj. Jen Kyseth, trains on her recumbent bike while her dog Mack waits by her side, Sumter, S.C., Sept. 15, 2014. Every time Kyseth trains on her bike, Mack is there with her as if he’s trying to show support which boosts her motivation. (U.S. Air Force photo by Airman 1st Class Diana M. Cossaboom/Released)