Merriman posted a reply to a video showing one young player being hit violently by another player, which attracted a lot of attention Tuesday on Twitter:
No further information about the youth football program shown in the video has been released.
Merriman earned the nickname "Lights Out" in high school after delivering multiple knockout blows. He went on to spend eight years in the NFL with the San Diego Chargers and Buffalo Bills before retiring in 2013.
The video Merriman replied to is difficult to watch because of how hard one of the youth players involved gets hit. The goal at that level should be focused on teaching technique and limiting hard contact as much as possible, especially in a practice environment.
A 2017 study showed 99 percent of brains studied from former NFL players features signs of chronic traumatic encephalopathy (CTE), a degenerative brain disease, but signs of CTE also showed up in 21 percent of brains from players who only reached the high school level of competition, per CNN's Daniella Emanuel.
Football is a hard-hitting sport that's also going to have risks, but coaches shouldn't be magnifying them for players just beginning to learn how to tackle properly.