So I’m preparing for my first ironman and formulating my nutrition plan. I’ve have been wearing my Garmin 910xt with HR quite a bit to gauge my sweat loss and other items. It gives me an estimate of calories burned, but how accurate is that? The other day I did a 15mile run, in 2 hours, and it said I burned 641 calories, that just seems a little low to me…I’m 5’8 155lbs, any thoughts / comments?
It’s not. Something’s recently changed and now it’s way low.
Dave
If you setup your profile correctly, give it a month or so to learn your abilities then it can be as accurate as any other on the fly estimator.
And THAT means that I’d still expect a 15% variance in what it says vs real life on any given day. Though it may be better in aggregate over the course of a month.
Sounds quite low to me. Just ran 1 hr…8 miles, I’m 6’2" 188lbs. Timex global trainer said 1132 calories. I have always wondered how accurate these devices were.
That sounds way low, like 50 percent low. I always back off about 10% from garmin’a number. I’ve been using it to track and lose weight for a while and I am down over 20 with calorie counting so I think what I do is about right
That sounds way low, like 50 percent low. I always back off about 10% from garmin’a number. I’ve been using it to track and lose weight for a while and I am down over 20 with calorie counting so I think what I do is about right
50% low was about my guess as well.
that is the equivelant of about 315w effort on the bike, does that sound reasonable to you? i seriously have no clue
So I’m preparing for my first ironman and formulating my nutrition plan. I’ve have been wearing my Garmin 910xt with HR quite a bit to gauge my sweat loss and other items. It gives me an estimate of calories burned, but how accurate is that? The other day I did a 15mile run, in 2 hours, and it said I burned 641 calories, that just seems a little low to me…I’m 5’8 155lbs, any thoughts / comments?
Ensure you have it set up correctly - Height/Weight - in the MyGarmin site. That might make it more accurate if you don’t already have it set up.
It’s not. Something’s recently changed and now it’s way low.
Dave
I noticed the same exact thing. Beginning a couple of months back. Calories now burn at a much slower rate, and after all workouts, the “calories from fat” reading is 0.
I had my metabolic profile uploaded from eNewLeaf, so when the readings started acting weird, I tried re-uploading my metabolic profile. Didn’t work. In fact that seemed to screw up other functions in my Gmin 310XT.
Anybody else have similar experiences? I ordered a replacement watch last week so I’m hoping the new refurbished one they send me won’t have any of these issues.
Cheers
No, it seems high. I would guess by 15 to 20%
At your weight I would think you would be very close to 100 cals/mile
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Beginning a couple of months back. Calories now burn at a much slower rate,…
Yup, a few months at least. It might have been longer. When was the last f/w update? I didn’t notice right away, but as I started counting calories to get back to my race weight in Feb, I picked up on the discrepancy.
Dave
At your weight I would think you would be very close to 100 cals/mile
That is the number I always heard. It can be a bit lower with a more efficient stride.
It seems to work well for me when I count calories and I’m a lot smaller than the OP
Disclaimer: I have no scientific backing for that number
jaretj
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100 calories is what ive always heard to, if anything my calorie count might be high based on my profile, which I suspected was at a higher weight, I just verified that I had 165 lbs in the profile…so shouldn’t that make the estimate higher? I can’t recall when I last updated, frankly Ive never worn the HR monitor a lot…only until I really started stressing out about the what/when/where of eating on the run…
Yea, no way is that right. I think a mile of running is something in the 105-110 calories/mile. Cycling…I have no clue. 15 miles, should be more than 50% of your 641.
Here’s a little chart from a 2005 article I read.
What’s the Burn? A Calorie Calculator
You can use the formulas below to determine your calorie-burn while running and walking. The “Net Calorie Burn” measures calories burned, minus basal metabolism. Scientists consider this the best way to evaluate the actual calorie-burn of any exercise. The walking formulas apply to speeds of 3 to 4 mph. At 5 mph and faster, walking burns more calories than running.
Your Total Calorie Burn/Mile
0.75 x your weight (in lbs.)
Your Net Calorie Burn/Mile
0.63 x your weight
My garmin profile has me at 5’11" and 145lbs. I put in my max HR and just used its suggested HR zones.
Some of my last few runs: (short/easy, long/easy, 5k race)
distance//pace//calories
4.8mi 8mm 455
11.23 8:28mm 1084
3.25 6:35 333
It averages right around 100cal/mile, a little more at race pace, a little less on easy runs.
I’m 6’2" 178 and burn about 130 calories a mile. I did notice last Saturday i did a 3 hour ride with almost 4k in climbing- my edge and Garmin connect reported 1200 calories and when i uploaded to Strava it reported 2300 calories which i think is pretty close to spot on… Not sure what is going on ?? Garmin connect has this AM’s run, 8 Mile run at 6:55 pace with two miles at Tempo, at 822 and Strava has it 1169. .
D
I’m not an exercise physiologist or anything, but I’ve heard/read that the formula for the average runner (setting aside efficiency) is to take your weight and multiply by .75 to get gross calories burned per mile. So if you weigh 175, you burn about 131 calories per mile and if you weigh 150, you burn about 112. This meshes with the conventional wisdom that the average runner (man/woman) burns about 100 per mile (if you assume that the average runner including men and women weighs about 135). BUT when tracking calories, you absolutely have to remember to track NET calories, not gross. If you’ve calculated your BMR (basal metabolic rate) of burning calories, you can figure how many calories you would have been burning just sitting around or going about your daily life. Let’s say that that is 75 calories per hour. So if you want to know what you’ve CHANGED in your calorie burn by running, take your calculated calorie burn from running and subtract the BMR burn for the time you’ve been running.
Example: I weigh 175 and have a BMR based on my age/weight/height of 1745 (72 per hour). With a relatively sedentary (but not totally sedentary) job, the calculations tell me to multiply BMR by 1.2 to calculate daily calorie needs to maintain weight (about 2100). Divide this by 24 and I get 87.5 per hour. I go for a run for an hour doing seven miles. At my weight I burn 131.25 per mile, resulting in 918.75 gross calories burned. But I would have burned somewhere between 72 and 87 per hour in daily life, so I subtract 80 from 918, resulting in 838 (or a NET of about 120 per mile).
Obviously, running faster burns a little more NET because you are replacing less time with running so you have less to subtract, but at that point you’re quibbling with numbers that aren’t exact anyway.
To the OP, at 155 lbs, my rough guess would be that you burn about 116 calories per mile GROSS and around 105 per mile NET of regular burn.
Not accurate at all. My buddy’s garmin has given him 5000+ calorie readings, on a ride that showed around 3000kj on his Powertap (which means the ride burned around 3000 cal).
I don’t ride with a Garmin personally, but I wouldn’t trust them for anything related to calories.
-Physiojoe