Fortunately, over the years, greater and greater emphasis has been placed on PT.
It was ugly, painful, and often done in combat boots. When we did PT, it was usually comprised of some simple calisthenics, the daily dozen, followed by a run at a fairly slow pace, called the airborne shuffle. In 1976 when I entered the Army, there was little if any emphasis placed on physical training (PT).
In my experience, however, this essential job requirement has not always been the case. Soldiers expect you to be able to “hang” with them physically and will be unforgiving if you cannot. As matter of fact, it is “sine qua non” to leadership effectiveness. In the military it is an essential job requirement to stay in good physical condition.