Tror jag har länkat till den här artikeln förut men tycker den ger en fingervisning om vilken typ av träning som går att direkt översätta till vandrings sammanhang..
"There were some interesting, and somewhat surprising findings among the research papers. Researchers found that when ruck loads exceed 40kg (typical military combat load):
Unloaded run performance does not seem to be related to ruck performance.
Run training alone has little impact on ruck performance.
Strength training alone improves ruck performance."

The Kettlebell Mile | StrongFirst
The Kettlebell Mile is the product of a two-decade long search for a way to simultaneously train strength and aerobic capacity. It seems so obvious now, but the best ideas are seen as such only in retrospect. I had much learning and tinkering to do first but finally, the science and my...
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"There were some interesting, and somewhat surprising findings among the research papers. Researchers found that when ruck loads exceed 40kg (typical military combat load):
Unloaded run performance does not seem to be related to ruck performance.
Run training alone has little impact on ruck performance.
Strength training alone improves ruck performance."