heart rate

http://www.heart.com/heart-rate-chart.html

Go to questions: What is a target zone?
And: How do I measure a Max HR?

That will tell you where you should be exercising dependent upon what your goal(s) is/are.


ETA: Based upon your age, and assuming you want to lose weight and improve your cardiovascular health, you'd want to exercise with your heart rate between 106-141 beats per minute.

Just keep your heart rate at something slightly under where you pass out. All that stuff about fat burning zones is bunk. Whe you first start getting fit your heart rate will be higher, it comes down with fitness.

Please, please, please don't believe this. It's not "bunk." This person has no idea what he or she is talking about.

As your heart rate increases, your body switches from burning primarily fat as a fuel source to a mixture of fat and glucose and then mainly glucose. At some point your body starts producing more lactic acid than it can process and it accumulates quickly.... thinking of trying to sprint for a long distance. Your body can only tolerate that so much and eventually you have to stop.

Anyway, there is a line of thinking out there that suggests, especially when first starting, you should only exercise at that aerobic threshold... where your body is burning primarily fat for fuel instead of glucose. But you have to do it over long distances. Over time, your body becomes much more efficient at burning fat and the amount of effort required to get your heart rate elevated will increase. At some point this process will plateau and you can start worrying about increasing your lactate threshold.

Here is a good discussion of the subject:
http://www.freedomsrun.org/Training/TrainingAerobic.aspx

225 - your age is a general rule of thumb for max HR while working out.

Someone should note, this doesn't mean you drop dead if you reach this heart rate. What this implies is that this is the maximum rate your heart will probably reach (varies slightly per person). If you reach this rate your going to tire out and need to stop or slow down within 5 minutes. You'll just run out of gas.

What heart rate should you exercise at? I'd say keep it as high as possible at a rate you can sustain for 30 minutes. If 150 wears you out in 15 minutes then slow it down a bit. The faster your heart beats, the faster you burn through calories and the more cardiovascular conditioning you'll be getting. That's the bottom line. Don't stress about fat loss zone or any other target zones people throw around. Just do the best workout for you. You should be able to carry on a light conversation during your routine. IIf you can't tell someone the time or mention what you had for dinner last night you're going to fast. If you can discuss in depth politics you're probably going too slow. Try to sit in between these two regions.

Personally I'm 41 and I typically sit around 165 for 40 minutes during workouts. Some days I push it up to 175 for the same period of time. It doesn't kill me. Riding a bike I don't go much over 145 because at that point my quads start burning. It really depends on what you're doing.

So depending on your current fitness level and goals, you can do a couple different things with your new training toy *ahem* TOOL.

The first thing I did with mine, because I could and was super excited, was a lactate threshold heart rate test. Mine was basic, I found a 1km track, mostly flat, and ran as fast as I could manage for 1 hour at a steady pace. My threshold was somewhere around 182, if I recall correctly, but the next day when I woke up to go to work I literally fell over upon getting out of bed - crawling around got me to a candy bar, which got me up and going. I was an idiot and didn't plan properly for it, I'm only slightly smarter now, I'd start with this site and a google search: http://www.beginnertriathlete.com/cms/article-detail.asp?articleid=633 Remember, your threshold will be different for each different activity (which is why they talk about a biking threshold and a running threshold), meaning you might get different zones for each activity. (not sure how much stock I put in that idea, but there it is).

Another thing you could do is compare the old "conversation" pace recommendations to what heart rate they actually are for you. I'm not sure what this would get you, other than remove the usefulness of occasionally babbling to yourself while working out, but it's something. I liked this article, which also introduces some other ideas to take into consideration: http://well.blogs.nytimes.com/2011/09/21/rethinking-the-exercise-talk-test/

The real information will come from tracking your workouts, heartrates, and progress. By playing with your heart rate training some, and paying careful attention to how you feel and how your body adapts and reacts, you'll be able to figure out if working for 30 minutes at 145 gives you the results you want, or if 125 is just as good, or if 15 minutes at 160 does you better (don't forget to factor in what you eat and when into the equation as well).

Oh, one side thought - I tried doing a lactate threshold heart rate test a few years later on a treadmill, and the treadmill kept picking up the signal and stopping the belt as I was getting my heart rate up where I wanted to be. I couldn't figure out how to disable this "safety feature", so I gave up. Maybe treadmills are smarter now, but I doubt it. YMMV.