When I start a hike, my hands and arms are free and easy. Towards the end I always find them clutching the straps of my backpack. Why?
Edit, for clarity: I always use a waist strap. I’m not talking about using my arms to lift weight off my shoulders. I seem to end up holding my shoulder straps, elbows pointed downwards, almost pulling the backpack downwards onto my shoulders and tighter against my back.
In: 310
When you pull on the straps, you shift weight forward a bit, sliding the center of mass closer to the center of your vertical axis. Lever rule idea. Make the angle between vertical center and the mass become smaller to reduce the sideward (backward) pull from the backpack. People also tend to hunch forward to offset that lateral pull.
Learned that lesson about being careful with weight distribution (and total) in the pack, a long time ago. Constantly fighting that backward pull is very tiring. Surprisingly so.
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