I thought somebody might find this interesting. I have been doing a ton of walking the past 6 months handing out fliers for my budding computer repair business which amounts to a lot of low intensity cardio. Because of this I haven't done any actual cardio at all during that time, except for warmups.
This morning for the hell of it I jumped on my stationery bike just to see where I was at. To my mild surprise I wound up doing 30 minutes on the same resistance at the same speed I used to only my heart rate was 20-25 bpm lower and I literally barely broke a sweat. During this time I've been doing very tough workouts which DO get my heart rate up to say the least.
My point is directed at people who may believe that hard weight training does not significantly improve aerobic capacity. I'm not saying I'm ready for a marathon or the Tour De France, but clearly my aerobic capacity improved noticeably. This wasn't Earth shattering news to me, but I was little surprised at how much.