HRM and calories

[tribogota]

Used my HRM for the first time cycling today. 90k ride (56 miles), 3hours 40mins, flat for half, up and down hills and one serious climb...1760 calories, CAN THIS BE RIGHT? It seems like way too much to me. Age 39, weight 135, 5" 6".

[tribogota]

How much over, 500 calories over, 1000?

[OakLeaf]

Depends on the model, and the conditions. The only way to know the error in your HRM would be for you to replicate the exact workout under laboratory conditions.

The more factors your software takes into account, the more accurate it's likely to be. Calculations based on speed and distance alone are the least accurate - adding in your weight, equipment weight, elevation change, HR, and power output make it progressively more accurate.

But even so, it's only a software estimation of something that can only be directly measured by analyzing your breath.

As I said in the other thread... it's useless to get so hung up about calories out, because there's no way in the world to measure calories in. (what your body actually processes)

[mirliluck]

Does your HRM have a chest strap ? If not, then I would be skeptical of the calories burned. But a nice HRM with chest strap that takes weight, age, min or max HR into account would be quite accurate. And I think 1760 cals for a 56 mile ride sounds totally reasonable. On my 1.5-2 hour rides I regularly burn in the neighborhood of 900-1200 cals so I think your total seems normal.

[GLC1968]

Another thing to keep in mind is that HR doesn't actually indicate calorie burn. Calorie burn is a heat measurement (at it's most basic) and HR doesn't necessarily have anything to do with heat. If you get scared or nervous (or sick), you could have an elevated HR and yet your actual calorie burn isn't any greater.

HRM for training is great, but it's only a tool and only as good as the algorithms within it! I've heard they are more accurate for men than for women, but again, it's an educated guess at best. In my case, I have an abnormally low HR and I do find that my HRM is pretty good at determining calorie burn in most cases. I have noticed that the longer I ride, the worse the accuracy is though. If you have a more elevated HR, then the calorie burn is likely going to be inflated.