Announcement

Collapse
No announcement yet.

Exercise Calorie Counters

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Exercise Calorie Counters

    This was a reply to John's post a few days ago, but I decided to make it it's own thread for visibility.

    I want to offer my opinion on exercise calorie monitoring: DON'T BELIEVE IT!

    1. The calculations are based on some sort of mathematical average written into the software. Average basically means that most bodies will burn calories at a rate higher OR lower than that number. The odds of you being average aren't great because...

    2. The software is written for able-bodied people who use more and larger muscles than us. An average person's one thigh may have more muscle mass than all of my triceps and biceps combined. Not to mention all the other muscles like stomach and back and calves, etc that would be engaged while biking or running.

    3. Poor calorie expenditure calculations will lead to overeating and weight gain. This study (and others, probably) show that people overestimate the calories they burn and underestimate the calories they eat. In fact, people in the study (in a laboratory setting) ate 2x to 3x more calories than they thought they burned!

    Next I'm going to show you some of my rides for comparison:

    John's Ride - 19.7 miles at 8.8 mph and 354 ft of elevation gain. 1,374 calories

    My Ride 1 - 39.5 miles at 11.3 mph and 0 ft of elevation gain. 1,042 calories
    I rode 2x as far as John at 1.3x the average speed and -354 elevation gain, but "burned" 332 fewer calories. He's a quad, I'm a para for whatever that's worth. I guess it's possible, but I don't really believe it.

    My Ride 2 - 30.6 miles at 9.5 mph and 1,072 ft of elevation gain. 751 calories
    Ten miles less than My Ride 1, sure. But +1000 feet of climbing and 300 fewer calories burned?

    My Ride 3 - 100.9 miles at 11.5 mph and 1,952 ft of elevation gain. 3193 calories
    Relative to My Ride 1 it's 2.5x the miles at 1x the speed and 3x the elevation and I burned 3x the calories.
    Relative to My Ride 2 it's 3.3x the miles at 1.2x the speed and 4.2x the elevation and I burned 4.2x the calories.
    Relative to John's ride it's 5.1x the miles at 1.3x the speed and 5.5x the elevation and I burned only 2.3x the calories.

    John's on Garmin and I'm on Strava and that just shows how different calculations can be between companies. I guess the caloric burn might be useable as a RELATIVE measurement between rides tracked on the same software, but I still don't trust the accuracy or absolute numbers.
    Also, Disclaimer: I did not have a heart rate monitor connected for any of my rides and John did for his. I have no idea what difference that makes

    In summary, I'm not a medical professional, but these numbers don't make sense to me. Combined with the variables of how caloric expenditure is calculated, I don't trust ANY kind of exercise calorie counter and I suggest that you don't either. I don't believe it's accurate and overestimation can lead to weight gain.

    Can any of the nurses weigh in?

    I'm happy to be wrong about all of this, I just need facts and data showing otherwise. Does anyone have info about how SCI burn calories relative to ABs?

    Last edited by brian; 07-05-2017, 03:47 AM. Reason: correcting data

  • #2
    The numbers are approximations based on data available and, yes, the assumptions include being able-bodied. The estimates get better with a heart rate monitor and actually quite good if you add a power meter. Using a power meter, software can actually integrate torque and determine work (=energy) directly.

    If your goal is weight loss, just remember there's no weight loss without hunger. Never has been.

    For more fun link Strava to training peaks and Garmin. All will have different estimates.
    T3 complete since Sept 2015.

    Comment


    • #3
      So here's a good solution.
      Whatever ride you do, find a cyclist who rode the same route. Assuming comparable body+equipment mass (which is incorrect as the bicycle will be lighter) they will have done the same amount of work (aka calories).
      T3 complete since Sept 2015.

      Comment


      • #4
        https://caloriesburnedhq.com/calories-burned-biking/
        T3 complete since Sept 2015.

        Comment


        • #5
          with a hr monitor I think its a good ballpark. based on the link mize posted at 6'2 225 -150 minutes-30 miles an ab would burn 1822........
          Bike-on.com rep
          John@bike-on.com
          c4/5 inc funtioning c6. 28 yrs post.
          sponsored handcycle racer

          Comment


          • #6
            An HRM and working within optimum fat burning target zones would increase the accuracy.

            Comment


            • #7
              I find that I have to jack my calorie intake up to sustain a consistent 1-2 hour a daily exercise regimen. It's a calories in versus calories out game. If I can drop down to 1,750-1,900 calories per day consistently and push for 30-60 minutes a day, I successfully drop 1/2-1 pound a week @ 6'1", 215 lbs. After a month or two of success, I treat myself at night to two glasses of milk and about 10 Oreo cookies and put all the weight back on in a couple weeks. Lather, rinse, repeat.

              Back in the day when I was a runner and used a pedometer, I'd set my stride at 3 ft and then at 4ft. Surprisingly, when I set it at 4 ft I ran 33% farther.

              Comment


              • #8
                Originally posted by Mize View Post
                If your goal is weight loss, just remember there's no weight loss without hunger. Never has been.
                The study I linked was not about hunger or feeling full. It was about estimating calorie expenditure and intake. The test subjects were asked to estimate the calories they burned and then eat what they thought fulfilled that same amount of calories. It says that in the abstract I linked.


                Originally posted by Mize View Post
                The numbers are approximations based on data available and, yes, the assumptions include being able-bodied.

                Whatever ride you do, find a cyclist who rode the same route. Assuming comparable body+equipment mass (which is incorrect as the bicycle will be lighter) they will have done the same amount of work (aka calories).
                I'm confused by these two statements you made. In the first you say that the calculations are based on a person who has an extremely different muscle physiology than we do. In the second you suggest that we should evenly compare ourselves to them. Is that what you're really suggesting as far as an accurate way to measure SCI calorie expenditure?


                I went to that site and while it sounds very informative, I can't find any evidence it's written by a medical professional. It's not sponsored by a hospital, university, healthcare network, or government health agency. In fact, if you read the "site funding" section, they are funded by ads and product placement. Is that how you want to get your health information?

                The Author does not appear to have a medical degree. There are no studies or journals linked. The only section where the author does link to medical sources is in the "affect of age" part where he provides links to Mayo Clinic and NIH. Why doesn't he have similar references for all his other data?

                I'm not saying the article is completely false. This author may have done a lot of his own research before writing it. But we have no way of knowing if his sources are reliable. I'm saying it's wise to find reputable sources for any information you find on the internet. We live in an age of misinformation and your personal health is not an area you want simply believe one internet stranger, no matter how reasonable they sound.



                I agree with you all that an HRM and Power Meter will provide more accurate results. I have an HRM at home I use with my stationary trainer and will use it on my next ride (I'm out of town on business).

                Though even with that equipment, it's just a more accurate estimate. Since 84% of fat leaves your body as carbon dioxide you exhale, the only way to really know how many calories you're burning is to do a V02 test, like the calorie estimate study subjects did. That kind of test measures the oxygen and carbon dioxide you inhale and exhale.


                Can any of the nurses weigh in?
                Last edited by brian; 07-05-2017, 11:59 AM.

                Comment


                • #9
                  Here are two articles that provide data from separate journals. One study was led by a cardiologist at Stanford School of Medicine and the other was sponsored by Japan's national health institute. Both call into question the accuracy of calorie monitoring, even with a heart rate monitor.

                  http://www.npr.org/sections/health-s...uring-calories

                  http://www.runnersworld.com/sweat-sc...-calorie-count



                  I know everything I've been writing sounds somewhat aggressive. I don't mean this to come across as bashing an entire sector of exercise software. Just take the absolute calorie numbers with a large grain of salt.

                  I'm writing all this just in hopes you'll be more careful when you think to yourself, "My app says I burned X number of calories, I guess I can...

                  ...reward myself with fried chicken for dinner!"

                  ...have another helping of mashed potatoes!"
                  ...go out instead of eating in!"
                  ...get a large instead of a medium!"


                  Thinking like that can very easily lead to weight gain and health issues, whether you're AB or SCI.
                  Last edited by brian; 07-05-2017, 01:35 PM. Reason: added more delicious hypotheticals

                  Comment


                  • #10
                    dang i eat about 1000 al dayly that it as i am slow to burn even when able bodied i eat 1200 to 1500 max and i know i worked stalls horses tree limbs had 72 a to look after am i stayed a 5 till i was hurt

                    Comment


                    • #11
                      Oh, and if your means of exercise involves any sort of motorized assist, well that throws a HUGE variable into the calculations.

                      Comment


                      • #12
                        I'll try to explain a bit more.

                        "Calories" is the coloquial term for kilocalorie, aka kcal. Yes, every food "calorie" is actually 1000 real calories. Anyway, one kcal (same as "calorie") is the energy needed to heat one cubic centimeter of water one degree (Celsius). The kcal is a measure of "work" in physics terms and here's the important part: the work needed to move something a certain distance is the same no matter which way or how fast you do it.

                        So walking one mile does the same "work" as running one mile. As such the calories your body uses to walk or run 1 mile is the same. This is physics.

                        It follows, therefore, that moving the same distance in a wheelchair or handcycle also requires the same amount of work. So if I push my chair 5 miles or ride my handcycle that same route the "work" and calories burned are the same.

                        So if you ride your handcycle along side a friend on a regular bicycle and you both weigh the same and your bikes weigh the same and you ride the exact same route then the calories burned are the same. You will absolutely be feeling it more and it will be more difficult, but that's because you're doing the same work with fewer and smaller muscles.

                        Math wise, work is the integral of force times distance. It takes more force to accelerate a heavy handcycle than it does a lightweight bicycle, so the reality is that the handcyclist of the same weight will burn more calories owing to the heavier bike.
                        T3 complete since Sept 2015.

                        Comment


                        • #13
                          Originally posted by brian View Post
                          Oh, and if your means of exercise involves any sort of motorized assist, well that throws a HUGE variable into the calculations.
                          I have a motorized assist on my handcycle. My plan is to replace my current cranks with a power meter crank from Quarq (I have two on racing bicycles from pre-accident, but they're the wrong BCD for the chainrings I'd need today). With power measured at the crank, I will be able to isolate the work that I'm doing vs. what the motor is doing.
                          T3 complete since Sept 2015.

                          Comment


                          • #14
                            Originally posted by Mize View Post
                            So if you ride your handcycle along side a friend on a regular bicycle and you both weigh the same and your bikes weigh the same and you ride the exact same route then the calories burned are the same. You will absolutely be feeling it more and it will be more difficult, but that's because you're doing the same work with fewer and smaller muscles.
                            Can you reference any studies that support this?

                            A 12 cylinder engine and a 6 cylinder engine can each move the same car the same distance, but I imagine they will use a differing amount of fuel to do it.



                            Originally posted by Mize View Post
                            With power measured at the crank, I will be able to isolate the work that I'm doing vs. what the motor is doing.
                            If you are ONLY using power at crank, then okay. But the software can't separate work like that when calculating it with speed and length of ride. The numbers still aren't accurate.


                            Again, I'm happy to be wrong about all of this. I just need data and reliable sources that say otherwise.

                            Comment


                            • #15
                              My statements about work required to move things can be found in literally every introductory Physics textbook. Energy and work are interchangeable in physics as they both represent the same thing.

                              If a 4-cylinder and an 8-cylinder car drive the identical route without stopping the 8-cylinder car will do more work because it is heavier. It is likely also less efficient as the amount of energy lost to simply creating heat will rise with the number of cylinders. Likewise a fat cyclist will have to do more work than a stick-cyclist.

                              So when a map-based estimate of calories is used they are essentially guessing at the total amount of vertical rise in the route and using your weight. This omits all the inefficiencies like that 8-cylinder creating more heat. It also omits aerodynamic effects. This is where heartrate comes in. Heartrate calories estimates are "better" because they include all the wasted effort from poor form or from stopping often (losing momentum). Heartrate isn't interested in the work required to move the bike, but rather the work that you used. There are many models for heartrate calorie burn but absolutely NONE of them is for wheelchair users. The best way to get that data is to hook wheelers up to a breath analyzer while they workout on a trainer. The breath analyzer looks for chemical byproducts of metabolism and can thereby be used to create a better heartrate model.

                              With power meters they are directly measuring the torque applied by the user to the cranks. There is no better measure for calculating applied work. They're just really expensive!
                              T3 complete since Sept 2015.

                              Comment

                              Working...
                              X