Heart rate monitors - calories burnt on bike and calories burnt on a run

2 watchers

Mungo Shuntbox Jun 2013 11:53am, 1 Jun 2013 First-time poster!!	0 Mungo Shuntbox 'ning I've used a heart rate monitor for training for three or more years now, very useful, etc. I know the calories burnt figures should be treated with a little bit of caution, but generally, I've found when I run, the calories burnt bit usually reflects accurately the work put in. However - on a bike ride I seem to burn many more calories. Per example, did just under two hours road biking yesterday, didn't flog it at all, average rate 145bpm, looked at the scenery, waved to ramblers etc. Burnt 2,700 kCalories. I looked at my runs, and for around 2 hours of make yourself sick fell running I was using up 1,500 kCalories at the most. So what's going on? Am I going to turn into a wraith if I keep cycling or is there something that makes a HRM inaccurate on a bike? Fanks for any thoughts.
Canute Jun 2013 12:40pm, 1 Jun 2013 637 posts	0 Canute Welcome to Fetch forums. As you no doubt know, the exact energy cost for both running and cycling depends on body weight and other variables, but 1500 Kcal for 2 hours of moderately demanding running would be a reasonable estimate. 2700 for 2 hours of easy cycling is almost certainly an over-estimate. See tribology-abc.com
Mungo Shuntbox Jun 2013 8:01pm, 1 Jun 2013 2 posts	0 Mungo Shuntbox Canute thanks very much for that link - it gave me a much more realistic figure for calories burnt. I am guessing that the calculator Garmin uses is based on energy use in running, and that using a compound of heart rate, weight, etc only works for running, but I wonder if somehow they've built either distance or height into this equation as well; that's the only way I can see why 145bpm over 2 hours is estimated to burn 2,700 kcal whereas running for 2 hours at 165bpm only burns off 1,500.
Canute Jun 2013 11:46pm, 1 Jun 2013 638 posts	0 Canute I do not use a Garmin, but I understand that there are various different ways in which Garmin can estimate calories. The most accurate is based on beat-to-beat measurement of HR, using an algorithm developed by First Beat Technology. This is usually considered to be as accurate as can be achieved without the need for individual laboratory measurements. I understand that factors such as estimated fitness level are taken into account (in addition to weight, height etc). I assume that Garmin automatically selects the best method of computing calories based on the information available, but I wonder whether or not it might have defaulted to a less accurate calculation, such as one based on distance.
mick173 Jun 2013 11:55pm, 1 Jun 2013 94 posts	0 mick173 hi MS I use a garmin 310 and my monitor calculates my cycling at about half the calories compared to running
Mungo Shuntbox Jun 2013 12:21pm, 2 Jun 2013 3 posts	0 Mungo Shuntbox O Rex Canute, salve! Yes you gave me the right direction to look in; it's all on this page here: dcrainmaker.com But here's the nugget I was looking for.. "It also should be noted that the second-generation of the Firstbeat algorithm is only applicable to running currently, and isn’t used in the cycling products yet." So basically, my Forerunner is set up to work out calorie burn on running alone. I've noted though that my girlfriend who has a newer Garmin (110 I think) seems to get a realistic result on her bike rides. I'll have a scratch around for software updates etc, but I think the case is solved. Many thanks guys - all I need to do now is to work out how to convert my bike calories result into a normalised one....
Mungo Shuntbox Jun 2013 12:47pm, 2 Jun 2013 4 posts	0 Mungo Shuntbox Small hupdate that may affect Garmin 405 owners like myself.... as Canute says, it does allow you to switch been running mode and cycling mode. I'd not noticed this when I read the manual 4 years ago, so again thanks for reminding me of it. If you want to know how to do it, here's a nice video with funky music: http://www.youtube.com/watch?v=P14mM5zUnes
Mungo Shuntbox Jun 2013 8:28pm, 5 Jun 2013 6 posts	0 Mungo Shuntbox Smaller hupdate switched Garmin 405 to Cycle mode and it made cock all difference.