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Musings on exercise - John [entries|archive|friends|userinfo]

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Musings on exercise [Jan. 24th, 2009|03:56 pm]
As I was jogging today, I think I realized why interval training works well.

See, if you want your heart to get strong, you have to knock it out of its comfort zone. You can't bring your heart rate up to a comfortable rate and expect it to get really strong.

Okay, but... once your heart rate gets to a certain point, you feel like crap! That's because your heart is overworked; it can't supply enough blood to meet your oxygen demands. (NB: Obviously, if you breathe more efficiently, it'll help here[1].)

I think that if you try to find a comfortable aerobic spot, you'll tend to end up not working your heart hard enough to strengthen it. This is great if your heart is already strong, mind you... if you can, e.g., jog for a few miles, you've got a good, strong heart, and it's certainly not going to become weak just because you find a comfortable jogging speed and stick to it. But you won't really make it much stronger, unless you push yourself out of that comfort zone.

Ah... but when you push out of the comfort zone, it's making you uncomfortable. Which isn't an inherently bad thing, but it does mean you'll be relieved when you stop, and that means you'll be eager to stop.

Whereas interval training, sure, it's going to be uncomfortable as well, but for a specific, set time that you know you can handle. (And intervals are frequently short - as short as 30 seconds.)

Can you guess how *I* exercised today?

Off to rest. Thank heavens I discovered that Netflix has Doctor Who on "Play Now".

[1] Note to self - remember to practice breathing when you're *not* exercising. Trying to remember to engage your diaphragm is a lot harder when you're already huffing and puffing.