1,000 Box Step-Ups (20 in)
Wear a Ruck Pack (45/35 lb)
Complete 1,000 box step ups for time. Use a 20 inch box and wear a ruck pack that weighs 45 lbs for men, and 35 lbs for women.

A ruck is a weighted backpack to simulate the gear carried during a hiking expedition.

Score is the time it takes to complete all 1,000 repetitions.
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