Observation/Question about: Unbreakable (not a spoiler)

I noticed that when Bruce Willis was lifting weights in the movie, he didn’t wrap his thumbs around the bar. Any weightlifters out there? I was always taught in High School that you MUST wrap your hands around the bar for safety! Any comments on this?

Oh, and if this has been covered, I apologize. I didn’t do a search first.

I noticed it also, but was more impressed with the paint buckets.

Didn’t the weight bar get progressivly longer as well?