Marietta's coaches often shift practices to the evening to avoid the intense afternoon heat. Or the players often take the field in helmets and football pants, leaving their shoulder pads on the sideline. As the wet bulb globe temperature reading falls, they'll strap on their shoulder pads for full contact practice. A 2007 study by Georgia Tech found that taking shoulder pads off helps the body keep its core cool.
"We were working with stricter guidelines before and we never cancelled a practice," Hopp said. And that's not because players in the northern half of the state have an easier climate for practice, Hopp said. "When you're looking at the wet bulb globe temperature, across the state it only varies by a couple of degrees."
Since 2003, the National Collegiate Athletic Association has operated under rules similar to those now in place in Georgia. Players not only had fewer cases of exertional heat illnesses, but their orthopedic injury rate also improved.
"It's been a real positive on the collegiate level," said Michael Ferrara, an athletic trainer at the University of Georgia and co-author of the study that informed Georgia's heat rules. "Our guess is the same thing is going to happen on the high school level, that you're going to see a reduction in the number of injuries around this preseason period, ... and still go forward with a great football season."
Including Georgia, seven states have adopted heat safety standards similar to the NCAA and NFL: Arkansas, Arizona, Connecticut, North Carolina, New Jersey and Texas, according to the Koery Stringer Institute.
A quick knee and a swig of water
To see how the risk of heat-related illnesses will change under Georgia's new rules, the GHSA has agreed to fund Cooper and Ferrara's research for three additional years.
"We need to be really careful that we don't assume that even with all the safeguards and precautions that followed, that we're going to avoid any instances of heat illness," said GHSA Executive Director Ralph Swearngin. "What we are hoping is that we will keep them at a minor level because we're aware of what to look for."
At Camden County High School, the beginning of the Aug. 2 practice looked more like a chaotic dance rehearsal, except for the large lineman crawling to the center of the field, sans hands, because he was late for practice. There was little contact, though the players were in full pads. Linemen, however, practiced their footwork without helmets during one drill. Players took breaks nearly every 10 minutes. Some breaks were brief, just a quick knee and a swig of water. For longer breaks, players huddled under shade.
Then the hitting began. A chorus of barking coaches rose and fell with each jarring collision. Dozens of parents in the parking lot formed an unblinking audience. Water was available as players rotated in and out of the huddle. Helmets did not come off.
The players are concerned about getting enough reps, but they're confident they'll be ready, even as they prepare to play a team from Florida that doesn't play by the same heat rules.
"I feel like it kind of set us back," said Brice Ramsey, the team's senior quarterback, who has committed to play college football at the University of Georgia. "Over the summers the last couple of years we were in shoulder pads and going to camps and stuff. This year we had to wear no pads and weren't in helmets half the time."
Senior fullback Jaccob Johnson said that, to make up, "we're just practicing harder, going at everything 100 percent and trying our best."
That drive to shine under the Friday night lights is so powerful that some players put in overtime, never mind the heat and humidity. The heat rules apply only to coach supervised practice. What players do on their own time is unregulated.