Mostly just shorter, with better medical care for those injured or falling out. The old death marches I heard used to be ~40 miles, while these days they tend t

Mostly just shorter, with better medical care for those injured or falling out. The old death marches I heard used to be ~40 miles, while these days they tend to be ~12 or less depending (big difference between 12 miles on the coast of Pendleton vs 12 miles in the 115 degree mojave desert). Yes, the boot have improved dramatically as well.