BETHLEHEM, Pa. - Philadelphia Eagles defensive tackle Antonio Dixon walked slowly off the football fields at Lehigh University on Friday afternoon.

The team had just completed its sixth full-contact session since first donning shoulder pads and helmets last Saturday. His face was covered with sweat and dirt. His uniform was soaked, as if he had taken a dip in the swimming pool across the street.

He managed a smile but was otherwise too tired to talk.

"It's been real intense," safety Nate Allen said. "With the heat and as hard as we work, it's definitely a grind. It's been a rough camp because of the elements, the heat, and doing everything in the midday sun. The guys are dehydrated, start sweating a lot and your muscles start to go. But you just have to fight through it. That's what training camp is about. It's all part of developing the mental toughness you need for the season."

Thursday and Friday were particularly tough days for the players. Allen was among the players forced to leave Thursday's practice early with heat-related cramping and wound up sitting out Friday's workout as a precaution. Running back LeSean McCoy also left early Thursday.

On Friday morning, the video board outside the locker room read 76 degrees. By 1 p.m., it was up to 89 and had climbed to 91 by 4 p.m., an hour into the afternoon practice. No one was forced to leave, but players were struggling to get off the field when the practice finally ended at 5:15.

A couple of players have gotten sick on the sideline since the intense practices began, most notably wide receiver DeSean Jackson.

"It's been very tough," defensive end Darryl Tapp said. "You just have to dig deep, try to focus on what you're doing and keep pushing through it."

Still, coach Andy Reid has no plans to back off. The Eagles will continue their high-intensity afternoon practices - the Eagles used to hold them in the morning until Reid switched this year - until their mandatory day off Tuesday.

"The thing I can tell you is that it's football and we're going to get better at blocking and tackling by doing it this way and that's very important," Reid said. "The players have been very positive with it and they're pushing themselves through, which is important. In this day and age, these six days here (from Wednesday to Monday) are kind of the dog days that we were presented (by the NFL's 2011 collective bargaining agreement)."

Keeping their cool

The Eagles' most serious heat-relaed incident of recent years happened in 2008, when defensive end Chris Clemons was carried off the field on a stretcher and taken to the hospital with dehydration.

But the Eagles have always gone to great lengths to make sure the players avoid similar problems. Since 2006, trainer Rick Burkholder and his staff have measured the core temperature of players seemingly prone to heat-related troubles by having them ingest internal thermometers the night before practice. The next day, a member of the training staff tests the core temperature by pressing a hand-held device against the players' lower back at various times during practice and gets a reading of his body temperature.

Occasionally, there are conflicts. Defensive end Jason Babin suffered a strained calf muscle last Saturday, but the team could not give him an MRI until Monday, after the thermometer had passed through his system.

Reid said Friday that he switched the practice schedule so that the players would have more time to get hydrated before engaging in the grueling afternoon workouts.

"We've had a couple of guys that were dehydrated," Reid said. "But on the other hand of that, our numbers (of heat-related problems) are way down practicing in the afternoon compared to what they've been in past years in that category, which is a positive.

"The players are doing a good job of getting themselves up, getting the meals in and getting the liquids in before they fall asleep in between practices. They're at least keeping the liquids in and then once they wake up, they continue to do that. So, that's made for better numbers in that area for us in the afternoon practices."

The cold tub in the backyard of the locker rooms remains very popular with players as a way to help cope with the heat. After Friday's practice ended, approximately a dozen players were immersed in the 50-degree water.

Some went in up to their chests while others stopped at their waist.

They'll be back at it again today.

"It's definitely been tough, but I think it'll be good for us in the long run," wide receiver Jeremy Maclin said. "Coach Reid talked to us about staying focused through all this and I think we kind of know that. You can put the hard work in now and I think that will pay off for us during the season."

Extra points: Defensive tackle Fletcher Cox, the Eagles' first-round draft pick, was excused from Friday's practice for what the team termed personal reasons. Cox has left training camp and no return date is known. Cox also missed a few days of minicamp in June to attend the funeral of his cousin and close friend, Melvin Baker, who was killed in a car accident in Cox's hometown of Yazoo City, Miss.

The Eagles worked out two free agents Friday: former Indianapolis and Seattle linebacker Adrian Moten, and ex-New York Giants and Cleveland defensive end Ayanga Okpokowuruk. Neither player was signed as of Friday evening.

Contact David Weinberg:

609-272-7186