Calorie count using apple watch fitness app

Discussion in 'Apple Watch' started by ray737, Jun 17, 2015.

  1. ray737 macrumors 6502

    Sep 11, 2014
    Does anyone know why there's such a big difference in calories burned on Apple watch vs the actual machine used. Apple watch shows 460 calories burned vs stair stepper machine shows 940 cals.

  2. Newtons Apple macrumors Core

    Newtons Apple

    Mar 12, 2014
    Jacksonville, Florida
    How long are you on that stair stepper. It take one heck of a lot the burn of 940 calories, heck it take a lot to just burn off the 460!
  3. ray737 thread starter macrumors 6502

    Sep 11, 2014
  4. question fear macrumors 68020

    question fear

    Apr 10, 2003
    The "Garden" state
    Generally the measurements on the machine itself are far more inaccurate than from a heart rate monitor. I'd go with the lower number from the Watch, and honestly depending on effort even that seems slightly high, but it's far more accurate than the machine for sure.
  5. Julien macrumors G4


    Jun 30, 2007
    1) Apple only shows Active calories and the cardio mechanic is showing BMR (Resting) and Active combined.

    2) The cardio machine only know you weight so is far less accurate. The :apple:Watch does have more metrics and better algorithms to work with.

    3) All calories burned in cardio are estimates based on algorithms and are meant more as a guide. There is no way to determine with absolute accuracy how many calories you actually burn.
  6. Newtons Apple macrumors Core

    Newtons Apple

    Mar 12, 2014
    Jacksonville, Florida
    While neither are accurate. I would go with the watch on the calories as even a one hour workout on the stepper would be hard pressed to burn 940 calories. I would say the equipment make of the stair stepper is exaggerating the number of calories burned while using their equipment.

    I do an hour on the elliptical at 40% incline and burn about 300-325 calories. There are so many factors. A 100 pound person will burn way less calories than someone who is 250-300 lbs doing the same routine.
  7. ray737 thread starter macrumors 6502

    Sep 11, 2014
    Thanks for all the responses guys...I will say that most of the cardio machines I have used for an hour on high intensity typically does show in 800-900 was mentioned above it must be just the active calories the watch is calculating.
  8. LoopyFloop macrumors newbie


    Feb 2, 2016
    Well, it gave me 52 calories for 30 min so you should fee lucky. Avg heart rate of 164. I guess I have a few more hours to get to me 300 calorie goal. I'll post tomorrow when I'm there.
  9. IphoneIssues macrumors 65816

    Dec 30, 2010
    I'm going to say the watch is wrong. I'm a cardio addict, and I've now tested the watch out in a few different scenarios. Running on the treadmill, the machine and the watch are within less than 10 calories of each other.

    Tried it a few times on an elliptical, for hour-long periods. Watch was consistently behind the machine by around 200 calories, each time I finished. It was an elliptical with handlebars, meaning you place your hands on the bars and let your legs do all the work. I noticed when I took my hands off the handlebars and let my arms sway with my movement (arm with watch was moving more), and monitored things for a several minutes, I noticed my rate of calories being burned had increased a little.

    I wonder if I would end up with the same amount of calories burned, on both the machine and the watch, if I didn't alter the resistance level on the machine. I always crank up the resistance several levels. Maybe the watch just isn't too good at picking up resistance and taking it into account.

    I haven't yet tried the stairclimber, but it's very possible it could be off.
  10. nicho macrumors 68020

    Feb 15, 2008
    Do you program the machine when you get on to it?

    I very much doubt the machine is more accurate than the watch, as it is blind to many of the factors that add up to an accurate calorie calculation.

    By the way if your arms are stationary then you're not using a elliptical machine typically and therefore, clearly, the calculation will not be correct... It's like hopping backwards on the treadmill and expecting the Apple Watch to calculate it accurately.
  11. thedoc46 macrumors member

    Sep 22, 2015
    I'm going to say the machine is the more accurate. The machine is able to determine how much power you're putting in and is able to determine wattage used. It also probably asked you for your weight and age, as well as used a heart monitor. Your watch, well all that is able to monitor is blood flow and bpm, and that's often off, depending on how stiff your wrists are. I like to cycle a LOT and the watch seems fairly accurate on calorie count when doing a hard push outdoor cycle, (about 450 cal per 30mins) If choose an outdoor cycle, even though im on an elliptical it gets close to what the machine says. If i choose elliptical its around half of that. ?? go figure... I base my assumptions on how hard i'm working and my heart rate, at 43, if i can keep my HR in the low 160's, i'm pushing to 80% of my max and for a prolonged period. There's NO WAY i'm only burning 200 calories for 30mins. Also my cycle computer, and bluetooth HR monitor seem to all fall in line with each other... As in around 450 per 30mins when in the low 160's.
  12. exxxviii macrumors 65816


    May 20, 2015
    Ditto. I have done a few rounds of analytics looking at calorie calculation data from my Garmin watch, various stationary machines, and a number of online calorie calculators versus the Apple Watch. I have found that the AW can be accurate for running outdoors, but it seems almost arbitrary for other activities. And, there is evidence that the calculations have gross internal errors with base metabolic rate. After looking deeply into the data and doing a little research, I cannot trust the AW's calorie calculations.
  13. bripab007 macrumors 6502a

    Oct 12, 2009
    I can't imagine an hour on a stair stepper could burn nearly 1,000 calories. Of course it depends on weight and heart rate and other factors, but I'd wager it'd be closer to the 600-700 kcal range. Certainly more than 450 calories if you're keeping that heartrate up at 75%+ of maximum.
  14. nicho macrumors 68020

    Feb 15, 2008
    the last time i did an hour on the stair stepper, it was 738 active calories with a total of 861 according to my watch. i was 90kg at the time and i did 310 flights according to the machine in that time.

    how hard were you working, OP?
  15. exxxviii macrumors 65816


    May 20, 2015
    A non-obese, middle-aged man maintaining a zone 4 HR will likely burn 1,000 or more total calories per hour on a stair stepper. That is exercising a very large muscle group, so it is easy to burn a lot of calories. Now, if you are on a relaxed 120 beats per minute level of effort, then it probably is more on the order of 500 to 600 calories/hour. Not many people can maintain a zone 4 level of effort for an hour.
  16. bripab007 macrumors 6502a

    Oct 12, 2009
    You're right, I wasn't remembering some of my own stats correctly. I just looked back at some of my ~1hr jogs, and, being very non-obese and maintaining an average ~160bpm heart rate through the course of the run, I burned right around 1,000cal per hour.
  17. IphoneIssues macrumors 65816

    Dec 30, 2010
    Except I used the elliptical setting while using an elliptical. ;)

    Sorry, man. The watch just isn't accurate all the time.

  18. nicho macrumors 68020

    Feb 15, 2008
    Like I say if your hands aren't moving you aren't doing what the elliptical setting expects.

    Much the same as hooping backwards while on indoor run. Hope that makes sense to you the second time I say it. Elliptical expects arm movement, hence the results you found.
  19. IphoneIssues macrumors 65816

    Dec 30, 2010
    The watch is off, stationary or regular, like others have said. Accept this or not. The choice is yours :D
  20. nicho macrumors 68020

    Feb 15, 2008
    The body fat and muscle analyser at my gym estimates how many calories you'll burn in 30 minutes of a given exercise. The watch is very close.

    If you don't use it properly it'll never be correct.
  21. hatshepsut01 macrumors newbie

    Feb 4, 2016
    I'm inclined to agree that the watch is more likely to be off, esp on the elliptical. At the exact same average speed (usu. 51-55), incline (max), and resistance level (max) on the exact same machine, the watch will give me anywhere from 2 cal/min one day to 4+ cal/min the next day. I don't keep track of my heart rate, but I'm skeptical that it would vary that much from one day to the next for the same activity at the same intensity. The inconsistency there makes me distrust the watch's results. The ellipticals at my gym seem much more consistent in giving me around 600 cal for about an hour, with a little more or a little less depending on the avg speed. Even discounting BMR calories--let's say 200?--the watch seems low even at 4+ cal/min. Maybe I'm just that super fit? :D
  22. bjet767 macrumors 6502a

    Oct 2, 2010
    The truth is your stair stepper is probably way off.

    Calorie count is a function of many things, one of which is the amount of increased wattage you produce over your normal daily activities. A Tour de France rider burns about 1000 or more calories an hour extra during a race and are some of the thinnest pro's around. Typically in their "training" rides the number is closer to 600 calories and hour and they use relatively precise sensors to measure their wattage output.

    If you burn 10 extra calories a minute in your exercise program then you are doing very well. But the average recreational person in their "hard" routines would be closer to about 6-8 calories a minute additional burn.
  23. exxxviii, Feb 7, 2016
    Last edited: Feb 7, 2016

    exxxviii macrumors 65816


    May 20, 2015
    I have not read any specific science on Tour riders. But the cycling calorie calculators I have seen estimate well north of 1,000 calories/hour for a normal person riding above 20 MPH. Additionally, the running calculators I have seen and fitness watches, which the AW does seem to align with, estimate more than 1,000 calories/HR for a runner at an 8:30 pace. There must be some missing contextual data in that 1,000 calorie/HR Tour de France figure.
    This argument is using generalizations against people who have specific examples using their biometric inputs in high-end devices. Given the errors and inconsistencies I have found in the AW calorie calculation algorithms, I believe it is far more likely that the AW is in error.

    If you google "top calorie per minute exercises" you will find dozens of workouts that common people perform that are north of 10 calories per minute, including cycling, running, swimming, jump roping, step aerobics, racquetball, elliptical trainers, indoor rowing, etc.
  24. bjet767, Feb 7, 2016
    Last edited: Feb 7, 2016

    bjet767 macrumors 6502a

    Oct 2, 2010

    "But the cycling calorie calculators I have seen estimate well north of 1,000 calories/hour for a normal person riding above 20 MPH."

    I think I get the confusion. The difference is what we are talking about. When a cyclist talks about "calories it is basically kCal or kilo calories.

    "One calorie (with a lower case c) is the amount of energy required to heat 1 gram of water by 1°C. A kilocalorie is 1000 calories, and Calorie (with a capital C) and kilocalorie (Kcal) are synonyms. On food labels, nutrition facts are in terms of kilocalories/Calories. (Wikipedia)"

    The energy density of fat is 3500 kcals per pound of fat. This means one has to burn a huge number little cs to burn off a alb of fat.

    I don't know what you are reading but most of the non-wattage "calculators are way off to the point of almost double what is really being burned during a cycling event. Today's racer have wattage measuring devices which give a very accurate view of the actual real wattage that is being produced by a rider. There are even trainers which attache to a person's bike (Computrainer and Wahoo Snap and Kicker) and they same the same story. A normal recreation bicyclist who is "fit" will burn south of 600 calories an hour in a normal ride. An that is when they are cruising at 150 watts per hour as an average. The typical Tour rider will average about 250 watts per hour and push over 350 during a sustained effort. Of course the sprints and short attacks will approach and exceed 2000 watts for a very short time.

    The point is we think we are working hard (and we are considering most of us sit on our behinds all day) but a 45 minute work out at best normally only burns an extra 600 cals and in reality probably closer to 350-450. Hardly makes up for the extra 2000 calories we often eat in response to the effort.

    Sport science is real but the consumer devices we use often are there to stroke our egos and desires more than the reality of what they do.

    Check out Froome's time trial (a 26 mile solo effort to be the fastest rider) I believe his average wattage was less than 400 for the entire effort. BTW that is good and would put his caloric burn somewhere in the 1200 - 1500 range.

    Froome's estimated average wattage in a finale climb of the Tour (well less than an hour BTW) was 414 watts.

    From an article:

    "For the climb of La Pierre-Saint-Martin last week – estimated by Kerrison at 15.3km and taking about 41 and a half minutes – the Tour leader climbed with an average power of 414 watts."

    Here's the formula used by the people who make the wattage measuring device:

    ((average watts x time in sec) / 4.18 ) / 0.24 = kCal

    So (414 average watts * 2490 secs/4.18) /0.24 = 1028 Cal or kcal burn.

    note a Cal or kcal is 1000 calories (small c)

    So the winner of the Tour burned 1028 Cals in 41 minutes.

    The issue then are we talking about the little individual c or the one all sports pros use Cal or kcal?

    I'm referring to the latter

    BTW Frommels 41 minute effort burned up the equivalent of .29 lbs of fat.

    Wew I think I got all the numbers correct.

    So 150 watts an hour average =

    For one hour of effort: ((150 * 3600)/4.18) /0.24 = 538 Cals and hour, less than ten Cal and hour.

    The Fig Newton I just ate has 110 Calories (that is big C and not little c) which means for my 1 hour 150 watt ride I can eat over 4 and be caloric neutral.

    Now you know why the numbers don't match.

    Just so you know I am a senior road bike racer, use watt meters, those "devices" and programmer. I find the Apple Watch "health" metrics to be more consumer than pro. I am disappointed in the restrictions Apple has put on its use as a display device. It has potential but really is more a fashion than a tool for serious work out measurements.

    --- Post Merged, Feb 7, 2016 ---
    Just to add some to give a view on road cycling Watt usage:
    Note: These speeds and watts seem to be pretty close.

    Flat No Wind Smooth Road

    Watt speed Cal/Hr Cal/Min
    100 13.4 360 6
    150 16.5 538 9
    200 18.1 718 12
    250 19.6 897 15
    300 21.3 1076 18


    Normal people can't sustain 20+ mph on a road bike for an hour.

    Weight and mass play a part, but these numbers are typical for adult male riders.

    And one doesn't lose 1 lb of fat when they burn 3500 Cal, the body is more complicated than that.
    --- Post Merged, Feb 7, 2016 ---

    Unless we can get some actual wattage from the stair stepper it would appear your AW is closer to being more accurate.
  25. exxxviii macrumors 65816


    May 20, 2015
    I have been an endurance endurance athlete for decades, and I am a former bike racer from long ago. I am very familiar with kilocalories; that is not the confusion. Almost every endurance activity at a moderate level burns more than 10 calories (10 kCAl) per minute.

    Here is a simple data point from this afternoon. I just finished a 90 minute indoor ride on my high-end trainer with power. I also was wearing my Garmin 910XT and my Apple watch. All had the same biometric information, including heart rate. The Garmin calculated 1,431 calories. The trainer calculated 1,296 calories. The AW calculated 718 calories. I know my body, and I have hundreds of hours comparing levels of effort between sports. There is no way the AW is accurate compared to the other two. This same error is consistent with how the AW calculates calories on all other non-outdoor running activities I have assessed.

    If you are a senior rider with power, you should be getting wildly different data from your own rides and devices than you are writing about here. I just did a 14.4 calorie/minute ride on my trainer, and I was not pushing it that hard. I have only been riding again since December, so I hope to increase my power dramatically over the next two months. This was not an A-level effort by most people's standards.

    Almost every running calculator under the sun, and the AW, estimates running at around 150 calories/mile. So, it only takes an 8:30 pace to hit 10 calories/minute, and even slower if you are heavy and out of shape.

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