Cardiovascular means of or related to the heart and blood vessels.
We call “cardiovascular” exercises like jogging, swimming, rowing, elliptical, and others that don’t stress any one muscle or group too much so we can do it long enough to burn a lot of calories. People associate so-called cardiovascular exercise with losing weight.
I’ll grant that those exercises can burn through a lot of calories.
I’ve come to doubt their effectiveness at developing the heart, lung, and respiratory system effectively—not to say they hurt, but I don’t think they help as much as people think.
Building muscle usually requires stressing it. To build biceps, for example, you have to make your biceps exert as much force as they can. While not the only way, lifting weights does the job—specifically, in a program lifting as heavy weights as you can.
What doesn’t work
What doesn’t build biceps is to lift weights well below your limit, no matter how many times. If you can curl 30 pounds once or twice with proper form, then curling 10 pounds won’t build muscle, even if you do it 100 times.
The heart is a muscle. So-called cardiovascular exercises seem the equivalent of curling well below your limit. They may burn calories, but I don’t think they develop your heart as much as the equivalent of curling your limit.
(After burning a lot of calories, most people then conserve calories and eat more during the rest of the day, undoing the deficit that exercise created, so you have to do more than just that exercise if your goal is, say, to lose weight.)
What’s the equivalent of curling your limit?
High intensity intervals, in my experience.
In high intensity intervals, you push your heart and lungs to their limit. You stress them as you stress muscles when you lift weights.
My results? A borderline Olympic-level resting pulse:
Before intervals, I ran six marathons and competed in ultimate at nationals and worlds levels, but never got a resting heart rate that low, implying a heart that strong.
What should you do?
If you want to develop your cardiovascular system, do high intensity intervals.
If you prefer jogging, high intensity means all-out sprints for short bursts.
If you prefer swimming, do some all-out sprints. Same with rowing: all-out sprints.
I recommend burpees too. They don’t need equipment, trainers, weather, space, or nearly anything. I’m pretty sure doing them twice daily was the major force behind the low resting pulse.
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