Why isn't weight lifting the same thing as cardio/aerobics?

[Deja Q]

With my atrophied muscles, I'm risking muscle rebuilding and my heart gets a workout...

But I can only do a couple minutes at a time; but I do enough reps to accumulate at least 30 minutes a day.

And have been seeing results, albeit over time.

Should I be concentrating more on cardio; am I risking anything by opting to lift muscles and feel that heart beat?

(I did have a checkup a few months ago; even the ultrasound of the earth showed it in good shape - amazingly. :D )

[ellie]

1. I was reading

on another board about cardio and the emerging research is showing that interval cardio training is better for your heart than steady state aerobics. That being said, weight lifting can be considered cardio if the moves get your heart rate up. I was doing a cardio sculpt tape before I cycled off of it to add variety into my workouts, and it was a lot of running in place and doing moves like shoulder presses with weights. And, have you ever seen a Firm tape? Those are very cardio-weight based.

[meegbear]

2. Not answering the question directly, but along the similar lines ...

I have a question about what seems to be a fundamental contradiction in all the hype about the advantages of aerobic exercise on the one hand and the disadvantages of coffee and caffeine on the other. As I understand it, the idea in aerobic exercise is to get your heart pumping at an accelerated rate (say, 150 beats per minute) for a sustained period (say, half an hour). This supposedly strengthens your heart and enables it to beat at a slower rate the rest of the time. OK, but they also say coffee and caffeine are bad for you because (among other things) they make your heart pound too fast. Howcum it's good when aerobics makes your heart pound faster but bad when coffee does the same thing? Why can't you get a good workout by just trekking down to the local diner every morning and drinking a gallon of Maxwell House while doing the crossword puzzle in The New York Times? Or is this just another example of me-generation doublespeak? --Kathleen S., Washington

Cecil replies:

Katie, my little cactus flower, I admire your moral tenacity on this issue, but I'm afraid you've fallen victim to the same pernicious reductivism (God, how I love this litcrit mumbo-jumbo) that afflicts the nation's weight lifters. That is, you focus myopically on the parts (for you, the heart; for weight lifters, the chest and limb muscles) rather than the whole. This is typical retrograde low-tech Chevy Impala-type thinking. We nonlinear postindustrial children of the Information Age, however, know that the important thing is the Big Picture, the system--the cardiovascular and pulmonary systems, to be precise. The important thing in aerobics is not to get the heart alone pumping faster, but to get the entire complex of heart, lungs, blood, and whatnot operating at max efficiency. Aerobics instructors sometimes focus on the pulse (heartbeat) because it's a quick-and-dirty way of finding out how hard your body is working during an exercise session. But the true measure of a good workout, as described in Aerobics, the 1968 bible on this topic, is oxygen consumption. In laboratory tests, they have you breathe into an air bag to compute how efficiently your lungs are working. Then they correlate that with electrocardiograms and numerous other technological miracles to determine what shape your bod is in. Needless to say, such fancy gadgetry isn't available at the average track or health club, hence the reliance on shorthand indicators like pulse rate. But merely getting your heart pounding from caffeine is like turning up the idle on your cough-and-wheeze Ford instead of getting an overhaul--that is, you may achieve some short-term gains, but you're still headed for long-term ruin. Plus caffeine may raise your blood pressure and do all sorts of other untoward things.

On a related note, one of Cecil's many admirers here at Straight Dope World HQ has inquired whether a fat person who loses a lot of weight isn't better off than a person who's been skinny all his or her life, since the fat person has been doing years of involuntary weight lifting--i.e., hefting his lardbucket self around every day. A beguiling thought if true, but Cecil is obliged to report that, unfortunately, it ain't. As a rule, as obesity increases, activity decreases--fat people frequently feel tired because their bodies are trying to ease the strain on the vital organs. So while they're carting around a lot more weight than average, they move a lot less than average. The net result is that the fat person probably performs less heart-strengthening physical work than an ordinary person, and as a result his heart is in worse shape. But suppose some ambitious fat person made a point of exercising energetically despite his condition. And suppose that person managed not to die of a heart attack in the process. And suppose finally that he managed to take off a lot of weight very suddenly. That person might well have an admirably muscular heart--as long as he kept exercising. If he stopped, though, the heart muscles would lose tone within a few weeks. Also, the blood vessels of our formerly fat person would probably be coated with atherosclerotic plaque, meaning we're potentially talking Infarct City. Wherefore abandon these puppylike excuses for not exercising--I swear, only the Teeming Millions could come up with the Drip-Grind Diet--and hump it on out to the gym today.

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