That's a PR release dreamed up by the studio, most all creative writing. A wheelbarrow loaded with 600-700lbs, love to see him even budge it off the ground. Or swing a 20lbs sledge for a couple of reps. If any of that produced 20 lbs of muscle, than any day laborer, cable layer or truck tire changer should be ready for the next Mr O. If his weight was down to a unnatural 151 he just returned to regular good eating habits and followed the usual lifting workouts.Though he may have added a few unconventional moves now and than. Body tends to return to a former natural state and weight fairly quickly. This is all Hollywood hype to draw attention to his new movie.
Unconventional workout do and can give outstanding results. But all depends on the results you are working for like Strongman, Tri events, stamina sport, etc., adjusting your training (and equipment) accordingly.
Started to like Downey,jr work in Less Than Zero, when I was 15 or 16. A good actor makes it look easy, and he does in most cases. Good Luck.
