Weaving as a workout

This is traditional weaving, Ecuadorean style. After each row (warp? weft? I can't remember) the weaver leans back to use their body weight to tighten the threads. Imagine the abs!
I bought a length of woven alpaca cloth to patch the back of my alpaca coat, which has worn through. The coat is very light and warm, but doesn't seem to be too hardwearing.