KENT, Ohio — An Ohio coroner has ruled exertional heat stroke caused the death of a Kent State University football player after an offseason morning workout.

The Portage County coroner’s office released the findings of an autopsy of Tyler Heintz on Monday. Heintz died June 13 after being hospitalized following conditioning drills at Dix Stadium.

Kent State fired a strength and conditioning coach who was at the workout. It says he gave false information about his certification. The coach says he was upfront about his credentials and was working toward certification.

Heintz was an incoming freshman. He was recruited from Kenton High School as an offensive lineman.