I do agree w/ M@L, 162 bpm is a pretty high heart rate and I would expect more calories than 140 calories to be burned. Mine is usually around 125 or so for a moderate intensity 30 minute aerobics workout during which Spark says I burn 150 calories. Definitely look into the measurements and make sure they are correct.
162 is quite a high heart rate, and indicates quite an intense workout. Working out at that intensity will typically burn 600-800 calories per hour, so 312 sounds about right.
140 calories burned sounds much too little for that kind of heart rate.
One thing you may want to check is the weight settings on your HRM, whether you have entered your current weight correctly, and also the units of measure (pounds versus kilograms). My suspicion is that this is what the issue is. 1 kg = 2.2 lbs, and 140 x 2.2 = 308, which is almost exactly what the online calculators are telling you.
Fitness Minutes: (33,489)
3/24/13 10:10 A
I use it as a gauge just like sp tracker. Even if it is off a little it helps with the over all monitoring.
Fitness Minutes: (79,333)
3/24/13 10:03 A
You don't say what kind of activity you did. HRM's are pretty accurate in well-studied activities such as walking, running and cycling. Also, you should be rather not at the either extreme of the weight scale. Some medications can also change your heart rate artificially either by increasing or decreasing it. In short, you should be pretty close to being normal in every way for the HRM to produce the best result. In other situations they are not as reliable. For example, HRMs are pretty useless in those popular cardio-ST mixed workouts.
Fitness Minutes: (15,905)
9,717 3/22/13 10:16 P
I agree. Those calculators do not take into account your effort, your actual heart rate, your gender, any of that. In general, the HRM is going to give you the best, most accurate estimate you can outside of a lab.
Fitness Minutes: (3,567)
3/22/13 9:29 P
Thanks :). I'd MUCH rather under-estimate then over-estimate my calories burned.
3/22/13 9:25 P
I'd go with the HRM. If you programmed age, weight, sex, etc., it should be the most accurate. 312 calories in 30 minutes seems pretty high to me, depending on the activity. Keep in mind, too, that you averaged 162 for heart rate- the HRM was there for the whole thing and takes that into account. The websites likely don't.
Fitness Minutes: (3,567)
3/22/13 8:15 P
I just completed a 30 minute workout with an average heart rate of 162 (according to my HRM), and it says I burned about 140 calories. However I took my average heart rate and plugged it into a couple different calculators online and they all come out to about 312 calories. HUGE difference. Which one should I plug into my activity log? Thanks