...but for a more aerobic workout I prefer distance running. To each their own.
For Operation Iraqi 'Freedom', 929 of the 4409 military casualties, approximately 21%, are characterized as "Non-Hostile". I assume that the Department of Defense includes accidental deaths, friendly fire incidents, and other types of "unintentional" killings in their statistics because the victims are just as dead as those whose deaths are KIA, which presumably implies "Hostile".
Similarly, domestic casualties resulting from weapons fire by the police continue to be deaths. Certainly we don't generally regard the police forces in the United States as "hostile" to the citizenry (with some notable exceptions...are you out there Bull Connor?). However, members of the police are not immune to accidents, errors of judgment, overreaction, fear, or even, occasionally, malice. Usually, when members of the police are involved in actions that result in death(s), they are temporarily suspended or otherwise removed from active duty while an investigation occurs. The results of the investigation may result in vindication of the officer(s) actions or some other response, with filing of criminal charges in extreme cases.
For Slate gun death number 4410, the source article says:
Two officers involved in the shooting have been placed on routine administrative leave as the major case unit investigates.
Fort Worth police spokeswoman Tracey Knight called it a "horrible tragedy."
"It was horrible for the homeowner. A family has lost a loved one that can never be replaced," she said. "An officer has gone through an incident that no officer wants to go through."