I've been experimenting a lot with front and OH squats. I'll do a power clean, pump out some front squats, shoulder presses, and OH squats, and then I'll lower the weight. Lately, I won't take even a 1 minute break the entire hour I'm at the gym. Yeah, I feel like I'm going to puke half the time but my endurance is through the roof. I'm 30 and I'm probably in the best overall shape of my life. I don't go for 30 mile runs any more but who the hell needs to be able to run 30 miles?