COLUMBIA, Tenn. (WKRN) — With temperatures soaring into the 90s, firefighters have to guard against heat exhaustion and even heart attacks.

In Columbia, the dog days of summer mean a lot of sweat and physical fitness for firefighters who do circuit training every shift.

News 2 was there as firefighters, dressed in full turn out gear, boots, helmets, and air packs weighing 80 pounds, play basketball and bang on a tire with a sledgehammer. Firefighters also do pushups, battle ropes, and lift a heavy truck tire.

Assistant Chief Brian O’Cain of the Columbia Fire Department says staying physically fit can save your life when you are battling a blaze.

“It’s extreme. You are pushing yourself to the max. Everything under your gear will be soaking wet. You could take your shirt off and ring the sweat out of it.”

O’Cain tells News 2 that the NFPA recommends firefighters do 30 minutes of physical training each day.

The idea is to increase cardio and endurance to deal with the high heat of summer and the extreme temperatures of a burning building.

“Heart attack is the number one killer of firefighters due to everything we are talking about. If we get complacent, and don’t stay in good health and good shape, we get an alarm in the middle of a night, when we are sleeping and then go from zero to 100, and then go inside of a fire,” said O’Cain, “We are exhausting ourselves more than we would out here, because your adrenaline is up, and our workload is 110 percent.”

O’Cain says much of the training requires more endurance than physical strength.

Nashville Fire Department spokespeople tell News 2 that hot days are also a concern for Nashville’s fire department.

“During the summer months we take extra care to make sure our personnel are healthy as they respond to an incident scene. At the discretion of the incident commander, they will call for more personnel to respond to a scene,” said NFD spokesperson Joseph Pleasant, “This allows them to rotate personnel out of the active fire scene at shorter intervals. We also make sure our medic units on the scene monitor the vital signs of our personnel. They check their blood pressure and other vital statistics.”