​Wet-bulb readings, which NBA and NFL decision-makers have started to rely on more heavily, played a role in FIFA’s decision to add hydration breaks for World Cup 26 matches. Could these same readings also influence when and how the Philadelphia Eagles practice during training camp? The answer is yes—heat and humidity metrics are increasingly shaping scheduling, conditioning, and safety protocols across professional sports, including the NFL.
High wet-bulb temperatures aren’t simply a technical nuance. When the wet-bulb reading climbs into the upper 80s and beyond, research from institutions like Penn State and ClimateCheck indicates conditions can become life-threatening, even for healthy individuals such as NFL players. The body’s ability to shed heat through sweating and evaporation can be overwhelmed, raising the risk of heat exhaustion and heat stroke. With that in mind, teams like the Eagles are mindful of the thermometer and the clock during training camp.
The Philadelphia Eagles will hold camp at the Jefferson Health Training Complex beginning July 28, with fan viewing limited to a single public practice at Lincoln Financial Field on August 25. Like other NFL teams, the Eagles have established heat-management protocols intended to protect players during hot and humid conditions. In practice, that translates to scheduling adjustments, practice modifications, and contingency plans tied to wet-bulb readings and other heat-stress indicators.
To understand how heat is monitored, it helps to know what wet-bulb temperature is and why it matters. Meteorologists and health experts track this measure, which reflects both heat and humidity and signals when the body can no longer efficiently cool itself during physical activity. The National Weather Service describes wet-bulb globe temperature (WBGT) as a composite metric that blends air temperature, humidity, wind, sun angle, and cloud cover to gauge heat stress in direct sun. This goes beyond the simple heat index, which only accounts for temperature and humidity in shade. Higher wet-bulb values indicate more dangerous outdoor conditions, with pronounced risk for older adults, people with heart or lung conditions, and anyone engaging in strenuous work outside.
A practical way to measure wet-bulb is to use a standard thermometer wrapped with a wet cloth at the bulb. As water evaporates from the cloth, it cools the thermometer, simulating how sweat cools the skin. Heat-stress resources note that wet-bulb readings in the 70s are generally manageable for healthy individuals with normal precautions. But once readings reach the 80s—especially the mid- to upper-80s—the risk of heat illness increases rapidly, even for well-conditioned athletes. Wet-bulb values above roughly 86 degrees are considered hazardous, and readings near 90 can become life-threatening with prolonged exposure, underscoring the need for vigilant monitoring and responsive adjustments.
The debate around wet-bulb safety in football was highlighted by discussions involving players like Cole Beasley, who questioned why practices were paused or canceled in the face of high wet-bulb readings. While Beasley’s comments sparked conversation, the broader takeaway is clear: teams must weigh environmental conditions as they plan practice schedules, conditioning intensity, and recovery strategies.
So, how might the Eagles apply this in training camp? They can leverage wet-bulb data to tailor practice times to cooler parts of the day, increase hydration opportunities, adjust practice intensity, and incorporate more frequent downtime and cooling breaks when humidity and heat accumulate. They may also implement shaded or indoor drill rotations, enhanced monitoring for signs of heat stress among players, and clear thresholds for suspending or modifying activities. By integrating WBGT and wet-bulb readings into decision-making, the Eagles—and other NFL teams—aim to maintain competitive readiness while prioritizing player safety.
In short, the same science that informs hydration breaks and heat-management decisions in international soccer is increasingly guiding NFL training camp practices. Wet-bulb temperature, along with wind, sun exposure, and ambient temperature, helps determine when it’s prudent to push players hard, when to pull back, and when to pause altogether to prevent heat-related injuries. As climate patterns continue to intensify, teams like the Eagles will likely rely more on these readings to shape practice timing, structure, and safety protocols well before the regular season begins.