When you exercise a muscle, it causes some damage which the body rebuilds better than it was.
Is there damage that happens during aerobic exercise? How does my cardiovascular system build itself up (other than the heart, which is a muscle)?
I’m pretty sure that your blood produces more oxygen carrying cells that allows more oxygen to get to your muscles.
That’s part of it. It also produces more and bigger capillaries in the muscles.
OK, but what stimulates them to grow? Does a high oxygen demand cause damage that is rebuilt? How do the capillaries know they’re supposed to get bigger, and get more of them?
Interesting question. I used to have horrible asthma and a touch of high blood pressure. I remember I was using a steriod inhaler AND a rescue inhaler at least twice a day.
My doctor said, “you should exercise and that’ll take care of that high blood pressure.” I thought “yeah right, I can’t even cross a street sometimes my asthma is so bad.”
So I started out slow on a bike, I was hard pressed to do five minutes, it took me a year to work up to one hour. Now ironically, my blood pressure is still slightly elevated, the exercise didn’t help, but my asthma is almost cured. My breathing is 95% better. I can use the rescue inhaler once every other month and I never need the steriod inhaler anymore, so by running and exercising on bikes, treadmills, stairsteppers I was able to build lung capacity.
So in my case how did that happen.
It’s a fairly simple hormonal signal. Oxygen deprived tissue releases specific hormones, and those hormones trigger the growth of cells in blood vessels. Because the hormone level is highest in oxygen deprived tissue the blood vessels grow towards the deprived tissue. When the tissue is no longer oxygen deprived it no longer produces the hormone and vessel growth ceases.
The same process occurs when a blood vessel is severed or blocked and enables adjoining vessels to take over the function.
The explanation can be fairly complex, but it boils down to: lack of aerobic exercise causes decay. This is why some older folks have so many problems with balance, stamina, diabetes, etc. It doesn’t have to be that way. You have to get older, but you don’t have to decay. Your body constantly produces cytokine-6 (among other things), which is the master chemical for decay. The harder you exercise, the more of this is produced, which triggers the production of cytokine-10, which is the master chemical for repair and growth. If you don’t exercise, C-6 is still produced, but there is little to no C-10 produced to counteract it. Therefore, your body decays. Ideally, you want to combine aerobic workout with anaerobic weight lifting.