Go to a high school track for this one, or have a 400m loop figured out.
Work is 2 total laps with as much heavy stuff as you can carry. Sandbags, kettlbells, buckets, whatever.
If you can carry it all the way around a full lap it’s too light.
Every time you set it down, you run a full lap.
Work is done when all equipment you’re carrying makes it 2 full laps.
But it’s not done. Count up the total of number of laps you had to run, and then match it. As in… run it again.