Only once a week?
 

A friend of mine told me I should only be working each major muscle once a week. Is this something I should be doing? Don't I want to work each one out more to get faster results?

For natural bodybuilding 2-3 times a week seems to work best.

My advice is to not worry about muscle groups. Worry about working the entire body three times a week on nonconsecutive days for a while. Train the body, not bodyparts.

The more times you are able to do something [and recover], the more progress you'll make.

I aim to train my major muscles groups twice a week.