here's why I abandoned cardio:
not enough calories burned in a cardio session to make it really worthwhile. What most people dont consider is that you're gonna burn X calories per hour even if you dont do anything at all, and that you're gonna end up eating more because of the cardio you're doing (you will, you know it, admit it!), so it pretty much comes out a wash. Let's say you burn 500 calories an hour... you would have burned 100 or more anyway, and you'll end up eating at least 300 more...so, that hour on the elliptical machine, at best, gained you 100 calories... is it worth it? for 60 minutes of tedium?
cardio can be very hard on the body. bad for your joints, etc. there was an article in the NY Times recently about 80's aerobic instructors who can hardly walk now. And another one about the preponderance of marathon runners with bad hearts.
This one is the real kicker=> cardio takes up a hell of a lot of my time and is bloody boring as hell. getting to the gym, getting changed, doing it, getting showered, changed, etc. etc... there goes 2 hours or more of my day I could be doing something else all together more valuable.
strength training is actually better for you aerobically speaking than aerobics. I didnt believe it when I started but it does seem to be true. About six or seven months ago, I abandoned the six day a week aerobic workouts I had been doing faithfully for months, and found that 1) my weight didnt change, 2) I can still do the same workouts I was doing before, with ease (I test myself every once in awhile, just out of curiosity). And all I do is 2x25 minute weight training sessions per week. This, I gather, is because an aerobic exercise only works certain parts of the muscle, while strength training, particularly lifting heavy weights to failure, works the entire muscle, engaging all of your muscle fibers.
I like the hard muscles popping out all over my body. At 50 years old, I actually have (slightly) bulging pecs for the first time in my life, woo hooo!
and here's why I might start taking up some limited cardio again:
I think human beings are designed to move, and especially to run.
my life is too sendentary. I sit in an office all day, I walk a bit, I sit at home, etc. etc.
I sleep better when I do some aerobics.
It might be true that there are hormonal benefits to daily exercise. But then again, I might be getting enough with the brief but very intense weight training sessions I do, I dunno....
I dont think that short aerobic sessions will be too damaging to my body. It seems the problems appear when aerobics are taken to extreme, as in marathons, long triathlons, etc.
There is plenty of evidence that brief, intense, tabata style workouts can be an effective fat buring method.
I'm moving to a condo soon where a very nice gym will be just a few flights of stairs away..
I simply flat out like to run!