I cut my sessions from 1.5 hours for each muscle group to 45 min and I have gotten stronger and bigger than I have in months. It really depends on your intensity too. I kick-strarted a year-long bulk with 5 weeks of Epistane and after pct continued to do 16-18 sets for back, legs, and chest, 10-12 for arms, calves, and shoulders... Waaaayyyyy too much. I was sore,lethargic and appetite sucked for 6 months. I am seeing far better results with 5-6 sets for small groups and 8-10 for large. This is not including any light warm-up sets, and each set that I count is a set where I CANNOT perform another rep (usually in the 6-12 range depending on the bodypart) This is really all related to one is looking to bulk up and increase in size and strength. It seems like you are also trying to get cut to reveal abs also. Everyone will not agree on this... Although abs should be trained year round, I usually just focus on building mass and eating, and once I've bulked sufficiently, I'll focus on showing those abs off with what really matters: several months of dieting and ALOT of cardio(if I want to bulk up this century, it will likely be accompanied with a little bodyfat. Hope this helps, but check these forums on overtraining, most can build an incredible physique on 1 hour a day, 4 days a week.