Foreman was always underweight during the 60s and 70s, he was badly coached (Dick Saddler was a joke) and often dehydrated... His natural weight was around 235lbs, at 6'3... Clearly taller and fairly bigger than Liston, i'd say arms in the 19 inches range, rumored to have legit 20 inches, but imo not underweight and dehydrated as he was...