Are calorie counters on exercise equipment pretty much worthless?

[I may have asked this here before…]

My home bike broke (a Bladez model, when the main left axle broke off). I signed up for LA Fitness today (see other IMHO thread), and, on a workout which would have almost certainly been around 1500 calories on my old bike, the model I used only said 650 when I was done (after almost an hour’s worth of vigorous pedaling). It didn’t seem to matter what I did with the torque knob-low or high it still gave me a constant 12 calories per minute.

So is my thesis sound? Are there too many confounding factors to make such counters anywhere near accurate even if the designers of the equipment more or less know what they are doing?

At best, they’re only a rough estimate. At worst, you’re better off making up your own numbers.

How long was your 1500 cal. workout? That would have to be well over an hour to get into the realm of what an average person can do.
Just for perspective, 1500 calories burned in one hour of running would require covering 12-13 miles. Even a world class runner can barely cover 13 miles in a hour while racing. (Road record is 58:23)

You mean running, right? I think he’s talking about a bike. That said, 1500 calories in a hour is a pretty world-class workout.

From what I understand, professional cyclists burn something like 1000 to 1200 calories in an hour. If you’re in real good shape, you’re probably doing about the same.

It sounds like the bike at LA Fitness may not be reading the difficulty knob, but just going by the RPMs. And it goes by what the typical rider burns, which is much less than what you do.

My recent experience with stationary bikes (also at LA Fitness) is that the bikes are not calibrated. Perhaps they can’t be. On the bike I usually ride, If I have a real good workout, the calorie readout will be around 1300 calories after a very vigorous hour. On the bike next to it, doing the same workout, I’d “burn” 700 to 800 calories. This is because it’s much harder to pedal at the same resistance level, so I have to set it lower to do the same workout. My guess is that the real number is somewhere in between, probably in the range I quoted in the first paragraph. (These are bikes made by Star Trac.)

Yeah, I know. It’s just easier to relate total calories to running as wind resistance is a minor factor, unlike cycling.
But the point i was making was that 1500 in an hour was beyond a mere mortal.

I once spoke with a guy who worked on those body fat calculator features that scales have nowadays. I asked him whether it bothered him that those calculators were notoriously inaccurate and he replied that the thinking was that absolute accuracy was not that important and what they really focused on was relative accuracy.

It didn’t matter so much that the scale said 15% when you were actually at 20%, but it was important that when you went from 20% to 19.5%, the scale would now say 14.5%. This would allow people to understand how changes in their diet and behavior relates with their body fat.

I imagine similar thinking exists with calorie counters on exercise bikes. It’s helpful to think of them not as calories, but just as units and to understand that units are not comparable between bikes. You can then use this to plan it so you go on a 650 unit bike ride today and then a 670 unit bike ride tomorrow.

Of course, if it’s just calculating calories by multiplying time by 12, then it’s just a crappy calorie counter and you should ignore it.

I do ride the thing pretty vigorously-I know that the default setting I use on my (broken) bike mimics a slight incline-but that’s for ~4 minutes, at which point I crank it up to the max setting for two minutes. It says 50 calories burned per minute at the max setting (if I keep a decent pace, which I do).

Yeah that’s nuts.

A fit individual going all out, HIIT style, is maybe going through 20ish calories a minute. And that is not sustainable for anything other than short intervals.

Using the CDC estimates biking vigorously gets you burning at just under 10 calories a minute. Figure your decent pace hard effort for two minutes is likely more than 10 and less than 20 calories a minute.

Going by effort expended and weight you can come up with a good estimate with any one of a wide variety of on-line calculators, better if you go with heart rate too,* or you can get yourself one of the newer heart rate monitors that Bluetooths to your phone and uses your weight and heart rate to give a less poor estimate.

*That one gives me credit for about 18 calories a minute during my heart rate max. 50 … not possible.

The real problem with calorie counters on machines isn’t the error in estimation they make based upon some algorithm of work done, but the fact that for reducing fat and/or improving fitness–the goal of most people who track calories expended–has no direct relationship to the calories used during exercise. Many people look at the meter, see that they’ve “burned” 2000 calories (which is only a coarse estimate at best), and then assume that means that will offset any damage done by eating a Double Big Burger with Cheese Fries. The reality is that body composition–the proportions of fat and musculature–are not governed by calories consumed (which are just a measure of energy evailable in a bomb calorimeter) but by the quantity and balance of macronutrients (carbohydrates, proteins, fats) consumed and the basal (resting) metabolic rate (BMR), i.e. the rate at which your body consumes excess calories in the 23+ hours of the day that you are not exercising. Increasing the BMR is like compound interest; even a small bump of rate means a lot more excess calories being consumed over the entire day.

How do you increase your BMR? Just doing some kind of exercise does not inherently increase BMR; you need to actually improve fitness, and in particular, build muscle. I don’t mean bodybuilder-type muscles, as those guys need to consume an enormous amount of calories a day to maintain their musculature, but a good proportion of lean muscle that consumes nutrients and provides storage for glycogen, which both moderates glucose (blood sugar) levels and provides energy for vigorous exercise and activity through the day. The other way to improve BMR is by controlling what you eat; eating a large proportion or amount of carbohydrates which amplifies blood sugar and stimulates insulin response, which mucks up the body’s natural rhythm of storing and using fat reserves.

Running on a treadmill or an elliptical trainer for an hour accomplishes almost none of this, regardless of what calories are consumed, and unless you are spending two or three hours every day doing vigorous exercise, you just can’t burn off enough calories during your exercise period to control weight and fat accumulation. Developing good fitness, eating a well-balanced diet with an amount of carbohydrates with a high glucose index consistent with your level of activity, and maintaining a healthy level of activity throughout the day to get a good BMR (and therefore burn excess blood sugar throughout the day) is the only effective and consistent way to control body weight and composition.


My understanding is that the amount of calories burned will vary with your weight as well as your basal metabolic rate. If the equipment is not measuring this (or allowing you to input it) than it is an approximation at best. The more your weight or your BMR is significantly different than the norm, the more the estimate will be off.

Stranger, could you please provide some evidence for your statements? Not a web nutritionist or fitness guru but a real cite please.

I mean I am a big cheerleader for exercise and in particular for including intensity and resistance training, for lots of reasons, but changing resting metabolic rate by a significant amount?

Muscle burns a bit under 13 calories/pound/day at rest. 3 times more than fat but still, adding 5 pounds of muscle and losing the same amount of fat, hypothetically, will increase daily calories burned by BMR by about 50 calories. Compared to the calories burned by exercise itself and non-exercise activity during the day - insignificant. There is also the “after-burn” of exercise (also called EPOC - excess post-exercise oxygen consumption), not BMR, and also not a huge amount. That is tied to both intensity and duration of exercise.

Macronutrient composition of food? There is something called the thermic effect of food and therefore a relatively higher protein diet will cause more calories burned than a higher carb or fat diet as it takes more energy to digest the protein. Not actually an effect on RMR and the magnitude is not huge. Less than 100ish depending on diet composition.