tzan-I have done multiple sessions training the same muscle groups and training different muscle groups.Both have been productive.I suggest that if you are interested in this protocol, do a bit of experimenting.I find it quite humorous when people critisize this technique even though it has been proven to work.Not only do most people not even try this type of training before speaking negatively about it, they fail to follow common sense when implementing it.For example, you don't do two full sessions in one day.You split up the amount of work you do in one session, and apply it to two sessions.Now, alot of people I know train about 90 minutes per session.On a two a days schedule, I'll do a 30-40 min session in the morning, followed by a 15-25 min session in the evening.At the most, I'm still only training about an hour per day, which is less than they train.Yet this is still looked upon as overtraining.Whats more, I only do two a days for two weeks, followed by a week of regular training.This has helped in avoiding overtraining.
These are the guidelines endorsed by all proponents of this type of training.So how does this equate to overtraining?This type of training is definetly demanding, which is why alot of people probably avoid it.Between my personal experience and the research to back it up, I believe this type of training has merit.Experiment around with it if you want.If done intelligently, I'm sure you'll benefit from it.If you're interested, Charles Staley e-mailed me a few two a days programs that have been quite effective.If you're interested let me know.Good luck.