After a pair of acclimation days on Wednesday and Thursday, the Denver Broncos kicked off the first official day of training camp on Friday with about 800 fans in attendance (capacity has been reduced due to ongoing construction at their facility). Here are five quick takeaways following Day 1 of camp as we head into the weekend.

Practice one of Pittsburgh Steelers training camp is in the books and here are some of the best video highlights from the day.

SANTA CLARA -- The 49ers just finished Day 1 of training camp. One wide receiver decided not to hold out, another wide receiver pulled his hamstring, the franchise quarterback threw two interceptions, and the rookie first-round pick made a strong first impression.