Both get their hypertrophy mostly from time spend in the gym, not from the actual event. Especially bobsledders. They push the sled for 5sec and after that they are just "living weight".consider the leg development seen in downhill skiiers and bobsledders
So there's really a big difference between "chain-crawling" and crawling just with bodyweight? I've only used regular crawling so far. You must be getting weird looks doing the chain crawlsVery true. At home since I don't have a hill the backwards crawling while towing a 60# or 90# chain simulates the hill pretty good.
Advice on towing rigs for those of us short of time and handyman skills, please.