These are the only things that are going to keep you in any form of physical health as you get older. You can lift weights and do those sorts of "body building" things, but if you're not getting your ticker up to some sort of training zone rate and keeping it there for a while on a regular basis, you can look forward to some very unpleasant results. Unless you just happen to have the genes from that golden gene pool. Only one out of hundred do.
So, now that we've decided that we better get off our fat asses and do something about living until Dick Clark finally takes that dirt nap, how much is enough? Well, as old Willie Blake said so long ago, "You never know what's enough until you know what's too much."
My friend the cardiologist tells me that if you do 2 miles a day at a brisk pace, you're doing all you need to do to keep your heart healthy. (I don't think he knows that I always preface this little workout with 5 super large Slim Jims, a 6-pack of Busch, a huge hunk of extra-sharp cheddar cheese, and a bag of waffle chips.)
You do need to keep a watch on your heart rate when you do this, especially if you're not used to it. You can get your heart rate by placing your fingers to your neck and finding a pulse. (I do worry about some of you folks out there being able to do this. No, not place the fingers . . .) It's pretty hard to hold your fingers there for 60 seconds, so just take your pulse rate for 10 seconds and multiply it by 6. You will need a watch for this. As well as a private school elementary education.
In fact, why not just do what I did and go buy a nice heart monitor watch that you can wear when you're running or walking? It's only about $100, and an angioplasty will run you several grand. It has a little belt that you can put around your chest with a battery-operated sensor, and a watch that picks this up and tells you your heart rate at all times. You can wear it while having sex and find out why your partner refers to you as a zombie fuck at the office the next day!
So, if you want to do 2 miles a day and get your heart into a training zone, what heart rate are you looking for here? Here's the formula:
Take 220. Subtract your age. You want to have your heart rate at between 65% and 85% of that number for at least half an hour. Don't go above 85%. You will probably feel it if you do, but if you're not checking you can get in trouble here. You know the guys who you hear about each winter dropping dead while shoveling snow?
OK, now let's get out there and burn off some of this hostility I'm sensing around here!