Online calculators are a reasonable estimate for exercises like running or walking, as your speed is a pretty good estimate of exercise intensity. However, HRM's are a good measure of other cardio activities such as aerobics or gym equipment like the elliptical or stationary bike.
Although they are generally better than most other methods of calculating calories, they are not perfect. People with high blood pressure or certain medications can experience higher heart rates than the exercise itself warrants, which can lead an HRM to overestimate calories burned.
Personally, I have saved my money and not bought an HRM. If I want to know my heart rate, I'll stop for 10 seconds and check my pulse manually. But I know plenty of people who have found HRM's useful and even motivation (by reminding them to push themselves harder), so far be it for me to advise you against getting one.
Fitness Minutes: (15,322)
449 5/14/12 1:28 P
You will see a big difference in the number on your hrm compared to the machine. Some of them are more than 50% off. I love my HRM. It makes me accountable for my exerices. If I'm not exercising in the my range, I know I need to step it up.
Fitness Minutes: (35,097)
2,167 5/14/12 9:10 A
If you do conventional exercises like running, biking, elliptical and swimming, then they are very accurate. For other exercises such as those aerobics DVDs, the predictions have larger error, but still you can get a reasonable estimate.
There is really no other way of getting a good enough estimate for the cardio exercises that you do. Even SP predictions can be way off when you don't work out really hard. I would say that you need it, if you can, get one, and not a very cheap one either (about $100 should be enough to get a descent one e.g. a Polar).
Fitness Minutes: (14,252)
9,673 5/14/12 8:19 A
About as accurate as you can get without stepping in a lab. It's still an estimate, of course, but a heart rate monitor with a chest strap that tracks your weight, age, and gender is about the most accurate way to determine calories burned during your cardiovascular activities. You can't use it for strength or day-to-day activities, but it is worth the purchase!
Fitness Minutes: (62,815)
112 5/14/12 8:15 A
Kind of would like to get some opinions on these. Is this a pretty accurate gage of how many calories I am burning during a workout? Is it worth buying one?
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