Heintz was doing conditioning drills at Dix Stadium and was transported to a local hospital following the workout.
Record Courier reports that a cause of death has yet to be determined, and that Heintz will subsequently undergo an autopsy on Wednesday, June 14th.
The follwoing tweet was released by the Kenton Football Twitter Account.
The two-star recruit from Kenton, Ohio, had dreams of playing Division 1 college football, but they were cut short tragically. Both players were offensive linemen.
Kent State confirmed Heintz's passing on Tuesday evening but did not offer a cause of death.
Student-athletes at Kent State are required to meet with team doctors and must pass a physical before engaging in summer workouts on campus.
KentWired talked to several players who were at the practice with Heintz. He was taken to University Hospitals Portage Medical Center where doctors reportedly worked on him for two hours. A standout football player, who his teammates say was excited to play for KSU. His death was a result of cardiomegaly - an enlarged heart found at autopsy to be approximately twice the size of a normal heart, which led to a significant risk for an abnormal heartbeat, DePerro said in December 2014.