How schools decide when it’s too hot for practice

CABARRUS COUNTY, N.C. — As temperatures soar across the Charlotte area, school districts are relying on strict heat safety guidelines to protect student-athletes. Channel 9 climate reporter Michelle Alfini explains how officials use Wet-Bulb Globe Temperature (WBGT) readings to determine when practices must be modified, moved indoors or canceled altogether.

Jim Bazlucki manages Athletic Training for schools in Lincoln, Cabarrus, and Stanly counties.

“When questions come up, we’re always going to err on the side of caution,” Bazlucki said.

A few degrees can make a big difference, especially during the hottest weeks of the year.

“When we reach certain milestones and markers, we have to either alternate and change some of our practice settings or we have to cancel altogether,” he said.

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An instrument measures WBGT, including air temperature, direct sunlight, wind speed and humidity.

“It does a calculation based on all four of those numbers and gives us the most accurate scientific reading of how your body responds to the environment it’s in,” Bazlucki said.

The higher the number, the higher the risk of heat stroke.

In the upper 80s, athletes have frequent mandatory water breaks and practice without full pads.

When it’s 90 degrees, the North Carolina High School Athletics Association said all outdoor practice must be canceled or moved indoors.

“It’s specifically difficult for young people and children, who might not really understand what’s happening to their bodies,” said Jessica Murfree, UNC Professor of Exercise and Sports Science.

Murfree studies the impact of climate change on sports.

She said staying safe this season means being flexible about what’s possible on the hottest days.

“We’re seeing shifts or delays in start times of seasons,” Murfree said. “We’re seeing delays in start times of individual games and practices, moving them later into the evening.”

In North Carolina, conditions are measured on the field or practice court 30 minutes before the scheduled time.

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