KATY, Texas (Covering Katy News) — With Houston-area temperatures approaching triple digits, students back in school and fall sports and marching band practices already underway, a Houston Methodist sports medicine physician is urging student-athletes, parents and coaches to pay close attention to heat-related illness.
The warning comes as new University Interscholastic League heat safety requirements take effect for the 2026-27 school year, including mandatory use of Wet Bulb Globe Temperature, or WBGT, measurements to determine when outdoor athletic and marching band practices must be modified because of heat conditions.
Previously, the UIL recommended WBGT monitoring but did not require it.
Unlike a standard thermometer that measures only the air temperature, WBGT is intended to show how stressful outdoor conditions are on the body by also accounting for factors such as humidity, sunlight and wind.
"Extreme heat doesn't affect every athlete the same way, which is why relying on more than the temperature alone is so important," said Dr. Irvin Sulapas, a board-certified primary care sports medicine physician at Houston Methodist West Hospital. "The goal is to get a clearer picture of heat risk so students can compete safely."
What the new UIL heat rules actually require
Under the new rules, schools must check WBGT conditions within 15 minutes before an outdoor practice or workout begins. When heat conditions reach elevated levels set by the UIL, readings must be taken every 30 minutes during the practice.
As conditions become hotter, schools must increase rest and hydration, reduce workout time, modify equipment and, at the highest heat levels, end outdoor activity. Athletes must have unrestricted access to water during practices and rest breaks.
The requirements also apply to marching band activities and to covered or indoor practice areas that are not climate-controlled.
Katy ISD already uses WBGT heat guidelines
Katy ISD already has its own WBGT-based heat guidelines for athletics. The district's guidelines call for athletic trainers to measure environmental conditions before practice and impose progressively stricter limits as WBGT readings rise.
At higher readings, Katy ISD limits the length of workouts, requires additional rest breaks and restricts protective equipment. When the WBGT rises above 92.1, the district does not allow outdoor workouts and requires practices already underway to move indoors.
The district's guidelines also require an on-site rapid cooling zone, such as a tub or tarp, once heat conditions reach specified levels.
Schools must be prepared to rapidly cool students
At specified heat levels, schools also must have a rapid cooling area immediately available at practices and contests. That means having a way to quickly cool the entire body of a student suffering from heat illness, such as a cold-water immersion tub or an ice-water tarp.
Practices and games are treated differently
One important distinction for parents is that the mandatory WBGT practice limits do not automatically apply to games. The UIL recommends monitoring conditions and making changes when necessary, including adding hydration breaks, moving start times or rescheduling contests in extreme conditions. Rapid-cooling equipment is still required at games when heat conditions reach specified levels.
Recognizing heat exhaustion in student-athletes
Sulapas said recognizing the symptoms of heat-related illness early is important because a student's condition can become more serious if warning signs are ignored.
Symptoms of heat exhaustion can include fatigue, nausea, dizziness, muscle cramps, vomiting and confusion.
Heat exhaustion can progress to heat stroke, a potentially life-threatening medical emergency that requires immediate treatment.
The UIL describes exertional heat stroke as the leading cause of preventable death in high school athletics.
For parents, the new rules provide some concrete things to look for: heat conditions should be measured before practice, athletes should have unrestricted access to water, practices should change as heat risk increases and schools should be prepared to rapidly cool a student in a heat emergency.