There's more information about an Air Force Academy cadet who died after a physical fitness test at the school.
Edward Schmeltz collapsed after a 600-yard run in January and died soon after despite efforts to revive him.
Officials say a pre-existing heart condition caused his heart to collapse during the workout but their report also suggests problems with the school's defibrillator training program also contributed to his death.
Investigators found the device was in a mode that academy staffers weren't familiar with, causing confusion.
The school says it has since purchased new, easier to use defibrillators and reconfiguring the old ones until they can be replaced.