My time in ('86 - '91 Active, '91 - '93 Reserves) had the following formula:
0630 - 0730: morning formation/roll-call, then PT. PT varied, but was typically sets of push-ups, sit-ups, and 2-3 mile run. We’d change up with various sports occasionally.
0730 - 0900: personal hygeine, barracks cleanup, breakfast.
0900 - 1130: work call. What we did depended on the Training Schedule, and could be anything from vehicle maintenence, classroom training, day-trips to the woods for training, range time/weapons qualifications, “area beautification” (mow the grass, trim the hedges, paint the barracks, etc.).
1130 - 1300: lunch
1300 - 1630: same as 0900 - 1130.
1630 - : “Recall” formation, dismissed for the day. Leaders may have meetings holding them after 1630.
About every six months or so we would go to “The Field” with our tanks and Bradleys and do “Maneuver Training” (coordinating companies and battalions in complex tactical maneuvers) and/or Gunnery. Field excercise were designed to be chaotic and stressfull; you may go 2-3 days with only 1-2 hours of sleep here-or-there, but no more than 8 hours total in that time. Gunnery less so; no one wanted a half-awake gunner behind the triggers of 105mm cannons, 25mm chain-guns, or TOW missile launchers.
Also about every six months we would do “Q-Services” on our vehicles, which was a semi-aqnnual detailed maintenence inspection/test of our vehicles. It was a week-long, all-day affair, and we would rotate through one platoon at a time (HQ platoon would typically be folded into one of the line platoons for this), and we would skip PT and other formations to do this.
One of the biggest gripes from new soldiers are “Details,” wherein a group of soldiers might be tasked to do something outside the scope of their MOS duties, such as putting on an orange vest and picking up roadside litter on a six-mile stretch of road, or getting “detailed” to an ammo point for another unit that’s in “The Field,” breaking down crates of ammo for their Gunnery rotation.
And there’s always Guard Details to be done somewhere.
Basically, combat soldiers not actively engaged in warfare represent a massive amount of manpower available to accomplish the 1,001 niggling little tasks that need to be done, and anyone, anyone, was fair game.