Friday's camp workout was a war of attrition against blistering hot 92-degree temperatures and oppressive humidity. Several players, including rookie DE Ronnell Lewis, received IV fluids during practice to combat exhaustion and dehydration.

Despite the risk of players' facing heat-related issues, Jim Schwartz said the opportunity to train in extreme conditions will help Detroit's preparations. “[Detroit isn't] a hot weather city, so when we get nice hot, humid weather like this, it’s great to practice in,” Schwartz said. “It’s great for our conditioning.”

Undrafted Edwards earning respect: Undrafted rookie WR Patrick Edwards' solid effort during camp workouts has slowly moved him from a player who was simply fortunate to have an invite to camp, to a contender for Detroit's final WR spots. Edwards struggled with ball security early in camp, but he has overcome those issues in the last two Lions workouts. Edwards' biggest asset is his speed. His work earned him first-team reps Friday, and he could play an increased role as Detroit's first preseason game approaches.

OT Reiff's role increases: First-round draft pick OT Riley Reiff looks more comfortable with each training camp workout. After spending the first two days of camp on the third team, Reiff's workload has slowly increased. With starting OT Jeff Backus' reps limited as a precautionary measure against the heat, Reiff took his first extended reps with the first team. Reiff isn't ready to challenge for a starting role, but the speed with which he is learning the OL's scheme is an encouraging sign for the Lions' line depth.

Moore shows more skill: Undrafted free agent QB Kellen Moore had a decent workout Friday as he continues his transition from the spread offense at Boise State to a pro-style scheme. Moore's success with Boise State has attracted more attention than usual to the progress of a third QB. His throws featured more pace Friday than he's exhibited in other workouts, a sign that he's adjusting to the needs of an NFL offense. He faces a greater challenge to make the team than No. 3 QBs in past years, especially since teams no longer designate emergency QBs on gamedays. The elimination of the third QB gameday slot means Moore is competing for a position against players across all positions, and he has a long way to go to earn a roster place.

Follow John Kreger's Lions updates on Twitter: @cbssportsNFLDET and @JohnKreger.