Add 10% and drag it backwards x 80 feet.
Add 10% and drag it backwards x 60 feet.
Add 10% and drag it x backwards 50 feet.
Rest 7 minutes and repeat for a total of 3 rounds.
If you’re using a metal sled on pavement the weight will need to be MUCH higher than the percentages given. The weights recommended are for a rubber tire on rubber flooring…the resistance is VERY high. As a frame of reference the final drag should take 30+ seconds for 50 feet.