McKamey, a freshman, was airlifted to the University of Maryland Shock Trauma Unit in Baltimore and is receiving medical care, according to the school.
The school did not provide any further updates on McKamey's condition.
"The entire Naval Academy family is shaken by this turn of events and we are providing all the support we can to Will and his family," Navy said in a statement.
The 5-foot-9, 170-pound McKamey was named Mr. Football for the state of Tennessee in 2012.
According to the Knoxville News Sentinel, McKamey also collapsed during a 2012 game for Grace Christian Academy. He was airlifted to the hospital and stayed in its Intensive Care Unit for several days as bleeding and swelling in his brain were monitored. He did not require surgery.