Jonathan Lent will work out until he runs out of air.The Forsyth County firefighter has about 23 to 25 minutes before his tank hits empty.He can often be seen during his shift down time doing bear crawls, push-ups or running up and down the stairs in full gear at Station 14 on McFarland Parkway.Staying in shape could help save a life someday, but he also practiced recently for an annual competition.Lent took home top honors in late June from Dalton at the 28th Georgia Police and Fire Games.Completing the Toughest Firefighter obstacle course in 2:35 won him first place in his age group (30-35) and second overall.He said “a kid” topped his time by 4.6 seconds.“Everything that they simulate on the course, it relates directly to firefighting,” Lent said. “These are things we do weekly, monthly for training and to stay in shape.”The course involves climbing four flights of stairs with a 75-pound hose, then unrolling a hose by pulling it up the stairs, hammering a steel beam five feet, followed by dragging the fire hose for 100 feet.Finally, the firefighter drags a 155-pound dummy for 50 feet to cross the finish line, which Lent said is the most difficult part of the course.The whole time, he wears his full gear and breathes from the air tank.The physical exertion could push even the strongest man to the brink of exhaustion, but Lent thinks positively to make it through the challenges.“It’s short. It’s quick.