Convert Nordictrack revolutions to miles

!!d5t(HwBGM~$(KGrHqQOKjoEq4+Z!DEtBKy6!R3G!w~~_32We recently purchased a Nordictrack elliptical trainer.  The machine is pretty nice, but both my wife and I immediately noticed a major annoyance: there wasn’t any documentation about how many “miles” the elliptical travels over the course of a workout.  We’re both accustomed to that form of measurement; the number of revolutions per workout was essentially meaningless.

 

So I put on my 10th grade geometry hat and figured it out.  Here’s what I did. 

 

Goal:

 

Use simple geometry to determine how many Nordictrack revolutions equal one mile.

 

First, measure the radius (r) of the encased wheel (this is the distance from the center to the outer edge). For improved accuracy, I measured from the center to the middle of the axle that attaches to the foot platforms. On my machine, the radius was 10 inches.  But we really need the diameter, which is 2(r), or 20.

 

So, we have the first part of equation, diameter (d): 20 ”

 

In order to determine the distance that the wheel would travel if it rolled freely, I need to measure to know the circumference of the wheel. This is the total length as measured all the way around the wheel, like you would get if you wrapped a tape measure around it.

 

Here’s where the geometry comes into play: since I cannot wrap a tape measure around the wheel, I use this formula to calculate the circumference (C):

 

 C = d(PI)

 

PI is that weird number that you remember from school. I won’t even bother with any details; for this explanation we’ll just agree that it is an important number and we’ll say it is 3.14159265.

 

So, the equation starts to take specific form:

 

C = 20(3.14159265) or C = 62.831853″

 

Now that we have the C, we can calculate the miles per revolution. To do this, first convert C, which is in inches, to feet:

 

62.831853″ = 5.236′

 

Now we know that every time the wheel revolves one complete turn (a revolution), we theoretically have traveled 5.236 feet. How many equal a mile? One more calculation:

 

5280 feet / 5.236 feet = 1008.4 revolutions

 

So, to travel one mile on the Nordictrack you have to pedal 1008 (or so) revolutions.

 

Tags: , , , ,

  • Cindi

    I too have always wondered about the distance thing. I didn’t do the math stuff though…I just figured if I can run or ride a mile in ten minutes then I was doing the same on the elliptical. Hmmm! I sure like the 300 revolutions per mile vs. the over 1,000 per mile. Yikes! Either way…it is still a great work-out!

  • Cindi

    I too have always wondered about the distance thing. I didn’t do the math stuff though…I just figured if I can run or ride a mile in ten minutes then I was doing the same on the elliptical. Hmmm! I sure like the 300 revolutions per mile vs. the over 1,000 per mile. Yikes! Either way…it is still a great work-out!

  • Karen

    So, has anyone figured out the odometer yet? What the X 100 means?

  • Karen

    So, has anyone figured out the odometer yet? What the X 100 means?

  • Lisa

    Apparently not, I was hopeful someone would at least respond to it. Thanks!

  • Lisa

    Apparently not, I was hopeful someone would at least respond to it. Thanks!

  • John Minnihan

    Hey Lisa,

    The calcs I did on my Nordictrac work for me. If you notice that the overall mileage calculated on your machine varies w/ velocity, then the machine’s measuring technique is flawed – the rate at which “distance” is covered varies, but the distance *itself* does not. In other words, whether it takes you 20 minutes or 40 minutes to cover 2 miles, you still have covered 2 miles.

    This is clearly a topic that is very interesting to many people. I’m a bit surprised that the vendors don’t cover this better on their websites. I would start w/ my calcs (appiled to your machine) and then go from there.

  • https://freepository.com John Minnihan

    Hey Lisa,

    The calcs I did on my Nordictrac work for me. If you notice that the overall mileage calculated on your machine varies w/ velocity, then the machine’s measuring technique is flawed – the rate at which “distance” is covered varies, but the distance *itself* does not. In other words, whether it takes you 20 minutes or 40 minutes to cover 2 miles, you still have covered 2 miles.

    This is clearly a topic that is very interesting to many people. I’m a bit surprised that the vendors don’t cover this better on their websites. I would start w/ my calcs (appiled to your machine) and then go from there.

  • Sunny

    Hey thanks for figuring that out. I also have the 990 and have wondered that many times. To me the 300 revolutions makes one mile just seems like too low a number. I was thinking just as an experiment to try using my pedometer because that measures miles. I wasn’t sure how accurate that would be though.

  • Sunny

    Hey thanks for figuring that out. I also have the 990 and have wondered that many times. To me the 300 revolutions makes one mile just seems like too low a number. I was thinking just as an experiment to try using my pedometer because that measures miles. I wasn’t sure how accurate that would be though.

  • Mark

    Just wanted to note that if the figure of 300 revs/mile were correct, each full stride (revolution) would have to carry us 5,280′/300 revs = 17.6′/rev. Don’t think so. Using the figure of 1,008.4 revs yields 5,280′/1008.4 revs = 5.236′ (the same number calculated for the wheel circumference above) – to me, that seems much more realistic. I can see a full stride (allowing a given foot to travel the full elliptical path of the pedal once, which would translate to two steps – one left, one right – on land) carrying me 5+ feet. That seems like a perfectly reasonable estimate. So the 1,008 revs/mile number seems like a good one to me. Hope that helps.

  • Mark

    Just wanted to note that if the figure of 300 revs/mile were correct, each full stride (revolution) would have to carry us 5,280′/300 revs = 17.6′/rev. Don’t think so. Using the figure of 1,008.4 revs yields 5,280′/1008.4 revs = 5.236′ (the same number calculated for the wheel circumference above) – to me, that seems much more realistic. I can see a full stride (allowing a given foot to travel the full elliptical path of the pedal once, which would translate to two steps – one left, one right – on land) carrying me 5+ feet. That seems like a perfectly reasonable estimate. So the 1,008 revs/mile number seems like a good one to me. Hope that helps.

  • Mark

    @Karen: I’m not sure why in the world they do it that way, but I believe the x100 thing is part of the revolution count. For instance, if your odometer reads 250 x 100, then you multiply the two to get 25,000 revolutions. Seems like a strange way to do it though. Why doesn’t it just say “25,000″???

  • Mark

    @Karen: I’m not sure why in the world they do it that way, but I believe the x100 thing is part of the revolution count. For instance, if your odometer reads 250 x 100, then you multiply the two to get 25,000 revolutions. Seems like a strange way to do it though. Why doesn’t it just say “25,000″???

  • Pingback: Pogi Ako » Blog Archive » iFit - Week 1 - Day 2

  • Larry

    Ok, this isn’t all that scientific, but after reading all the posts here, I tried to do some logical deductions.

    I’m using the Nord 600 and the stride I measured is 18 in., so a revolution would be 3 ft. That would put a mile at 1760 revolutions. That seems a bit much to me, so I watched the track on the display as I was jogging. (the motion of the elliptical resembles a jog more so than the peddling of a bicycle ).

    Logically, if the designers of the elliptical calculated that the track should be a quarter mile, as is pretty much the standard, it was completed in 360 revolutions. Therefore, a mile would consist of 1440 revolutions.

    This, of course, is based on assumption and speculation. But it works for me and that’s what I’ll be using to calculate my mileage.

  • Larry

    Ok, this isn’t all that scientific, but after reading all the posts here, I tried to do some logical deductions.

    I’m using the Nord 600 and the stride I measured is 18 in., so a revolution would be 3 ft. That would put a mile at 1760 revolutions. That seems a bit much to me, so I watched the track on the display as I was jogging. (the motion of the elliptical resembles a jog more so than the peddling of a bicycle ).

    Logically, if the designers of the elliptical calculated that the track should be a quarter mile, as is pretty much the standard, it was completed in 360 revolutions. Therefore, a mile would consist of 1440 revolutions.

    This, of course, is based on assumption and speculation. But it works for me and that’s what I’ll be using to calculate my mileage.

  • John Minnihan

    This topic is getting a lot of mileage… now see, that’s funny.

    I advocate using whatever technique or values work for you. My technique & equation are based upon the wholly circular wheel that rotates when you pedal. In classic mileage calculations on a free-wheeling bicycle, that’s what is measured.

    So – pedal on!

  • https://freepository.com John Minnihan

    This topic is getting a lot of mileage… now see, that’s funny.

    I advocate using whatever technique or values work for you. My technique & equation are based upon the wholly circular wheel that rotates when you pedal. In classic mileage calculations on a free-wheeling bicycle, that’s what is measured.

    So – pedal on!

  • Larry

    Yes, you’re right John, this is getting funny, but all this calculation on our part shouldn’t be necessary. The makers of the Nordictrack should have provided their customers with this basic information in the manual.

  • Larry

    Yes, you’re right John, this is getting funny, but all this calculation on our part shouldn’t be necessary. The makers of the Nordictrack should have provided their customers with this basic information in the manual.

  • Confused

    I have a NordicTrack CX 1300 and have also been wondering this.

    I figure that you go 40″ every time one revolution goes by, because the machine's stride length is 20″ and I have two feet.

    40″ stride per revolution
    5280 feet/(40in/12) = 1584 revs per mile

    On the other hand, when you wonder how much the wheel has gone,

    Diameter of my wheel: 22.25 inches (self-calculated)
    5280ft*12ft/in = 63,360 inches per mile

    C = pi*d = pi*22.25 = 69.898
    = 906.464 revolutions per mile

    So I'm unsure of which should be considered the correct value. I would have thought these should have come out to be the same thing, no? When we calculate a bike don't we use the circumference? Why would you measure it based on what your feet were doing, rather than the output?

    Sincerely,
    Confused

  • John Minnihan

    This is a confusing topic because each machine is different and I've made the assumption here that “revolution” refers to the rotation of the wheel, while the manufacturers seem interested in measuring the stride of the pedals.

    Don't forget that the lateral stride increases or decreases when you adjust the pitch of your sliding pedals (which aren't really pedals at all) if yours are adjustable; mine are. So any calculations involving stride become immediately suspect. That's another reason why I choose to use the wheel as the authoritative element of measurement.

    Since the wheel is round (a perfect circle) & the pedals are delivering work in the form of rotation of that wheel (a traversal of the circumference of the circle), it makes sense to me to use the calculation I describe in the post.

    In my mind, since the miles travelled by the trainer are theoretical only, it is perfectly reasonable to use the measurement that makes the most sense to you & best meets your exercise goals.

  • Confused

    I discussed this issue a while with my brother. He said that measuring the stride using an ellipse is probably the most authoritative method. With this method, I measure a major and minor axis of motion and plug these axis lengths into an ellipse circumference calculator (google it).

    With this method I got close to 1500, vs 907, revs per mile.

    Our circumference-of-the-circle method was treating the elliptical like a huge bike, which it is not. But, that would definitely be the way to measure how far the elliptical would have gone if it was not stationary (imagine that).

    The stride method will give us a linear approximation but modeling the motion using an ellipse is even more accurate. I believe the elliptical measurement will also account for any incline, etc. But keep in mind that Work = Force*Distance. Just because the distance is the same doesn't mean the human body is doing the same work! So, none of these measurements prove anything except the distance part. The force of an elliptical and a treadmill is different on our body.

  • John Minnihan

    I'm amused that this post has generated so much interest over the past year…

    You've certainly put a lot of thought into this, and I am intrigued by the notion of elliptical circumference. This doesn't change (for me) the fact that the only “thing” rotating is the rear wheel to which the pedal mechanism is attached. As stated above, that's one of my basic assumptions.

    It would very interesting to study a video of someone using an elliptical trainer, and markup the frames of video to prove/disprove that the ellipse maintains the same size throughout a workout, without regard to adjusting the pedal mechanism.

  • Cannon91

    John, I think that's the difference between your calculation and the manufacturers. I too have a 990 and just got off. I looked at the odometer and it said 25. I was like ok, I'm going to figure out what the heck that means and I came accross your post (thank you). In comparing the explanations, it would appear that while the wheel revolution is important, one cannot discount the stride. It's either the wheel revolution or the stride (wheel up and down on the guide ramp). So in your example, you've calculated the revolution of the wheel, however it doesn't take into account the actual stride, that can vary, of the individual and I think it needs to. Imagine taking the two “pedals” and spacing them far apart. Each revolution of the wheel would result in two very large steps, possibly longer than the circle, correct? Somewhere in that is the answer but of course I agree that it cannot be exact because your foot placement ultimate determines the actual distance. I'm looking at the stride right now to ensure it's 18″, if not 20″. Then I calculate from there based on simple tests. Regardless of the elevation the stride appears to remain the same, as I've used a pencil to make the points of the wheel guide depending on the height. It first appeared that the stride changed but it was just the wheel moving in relation to the elevation, the length or “stride” appears to always be the same. So it's 1760/mile for 36″ strides or 1584/mile for 40″ strides, if that's what you feel is authoritative.

    Hey but in the end, if anyone doesn't agree, make it whatever you want as long as it motivates you right? I have a treadmill that WAAYYYYY over estimates calories burned. My wife and I still laugh at it but it became a great motivator in the end to see who could out do each other.

    Again, great post and thanks for sharing your calculations.

  • John Minnihan

    “…make it whatever you want as long as it motivates you right?

    Absolutely.

  • Joseph

    John thank god for guys like you I just spent over half an hour with Nordictrack asking them the same question and they had no answer….you rock!!!!!

  • Jerome

    Did anyone ever figure out what the odometer (X100) calculated and how?

  • polecat

    John, your math is correct, that is the distance traveled as far wheel rotation. The distance of one's stride is yet something else. An 18″ or 20″ stride is a linear number and serves no purpose in figuring an eliptical stride.

    The debate rages on.

  • T. Bannister

    We just bought a NordicTrack Audio 990 and, like so many others here, have wondered what distance we are “traveling”. In fact, when I did a web search on this question, this was the site that had the most rational discussion, so compliments to Mr. Minnihan and the others who have commented on this topic.

    With regard to pure distance travelled, I think the JH approach using the diameter of the wheel is the most accurate (though I measured 18 inches for the axle movement diameter, rather than 20 inches). The elliptical movement approach is interesting, but if that mimics the movement of our feet, we don't usually include the distance travelled by our feet as it arcs upward and downward as we run or hike, but rather the distance along the ground we have traveled; so, I fall back to the distance travelled by the wheel as it is translated to a linear distance (like a bicycle).

    Now, I wondered why my heart rate was so high after walking only 0.6 of a mile and in only 20 minutes. When you factor in an incline of only 10 degrees (the minimum angle setting), it is like climbing a hill 0.6 miles along the incline and an elevation gain of 550 feet. That is equivalent to a 55-story building! A distance of 0.6 miles on a perfectly flat surface is much different than climbing 0.6 mile along an incline that is 550 feet high.

    (The resistance setting I suppose is like simulating walking through snow, dry sand, or mud, so that's a whole other complication, but it doesnt effect distance.)

    So, that's my 2-cents.

  • Confused 2

    no sure on the distance – are the calculation based on riding a bike or running. There is a big diffence going 1 mile by running or riding a bike.

  • John Minnihan

    Thanks for the recent comments everyone.

    It would be great if manufacturers took this as cue to improve the information that they make available on their websites – clearly many people have this question. Even those folks that are generous enough to comment here don't completely agree on exactly how or what to measure to derive this piece of data.

    Hey NordicTrack – are you listening? We'd love to hear directly from you.

  • Misty

    Thank you so much for providing the information I was looking for. This is very helpful. When we set up our new elliptical Nordictrack, lack of knowledge of the miles was my only complaint so far. Have a wonderful weekend. Misty

  • Misty

    Thank you so much for providing the information I was looking for. This is very helpful. When we set up our new elliptical Nordictrack, lack of knowledge of the miles was my only complaint so far. Have a wonderful weekend. Misty

  • Becky

    Thank you!! This was very helpful!

  • nb

    Thank you!!!

  • nb

    The manual says that one complete cycle around the matrix (the track that is displayed is 1/4 mile), double check the count when the matrix goes blank (it does that after each completed lap) then multiple by 4, but I like the approx. 1000 count for now..

  • Bernadette

    Thank you so much!
    I should be able to figure mine out now!

  • kab

    I spoke with nordictrack about my 800 and they said count how many times your knees go up and 1760 = 1 mile

  • yennta

    Wow, thanks, all. I'll go with the 1008. Thanks, thanks.

  • KevinF

    I just bought an AudioStrider 990, like the original poster and I was wondering the same thing about the mileage. My first comment is I think you have to consider the stride length as if you are actually running. If you consider the wheel in the distance, then you are saying the machine is a bike with a 20″ diameter wheel. So, the real question becomes “Is the elliptical more like riding a standup bike or running on a smooth floating treadmill?”

    The one comment I can make about the numbers presented here concerns my normal running routines. I run 7.5 miles in an hour on a consistent basis 3 or 4 times a week. I was able to run 4400 revolutions in one hour on the 990 this morning, which is an average of 73.33 RPMs. According to John's original calculation of 1008.4 revs per mile, that means I ran 4.36 miles in an hour. If I use the stride length method that says I traveled 40 feet per revolution, I only ran 2.77 miles. If I use the answer from NoricTrack at 300 revs per mile, I ran 14.667 miles.

    I am not sure which one is correct, but I know I did not excert myself the same as running 7.5 miles. However, I certainly felt like I ran more than 2.77 miles. I know I am contradicting my original statement, so the answer may lie somewhere in between.

    Thanks for posting this a year ago. It has helped me conclude the elliptical machine total distance covered in an hour is not really related to how far I can run in the same amount of time. Due to my recent knee problem, I will continue to use it until I can get back out onto the road with the knowledge it is different, but still good for my heart. :-)

  • Amber19394

    Don't you also have to take into consideration the resistance that you use? Like a bike, the same stride will get you further on a harder resistance. I know this isn't a bike, but it uses some of the same concepts.

  • John Minnihan

    Hey Amber,

    You're right – friction would play a role in a real bicycle situation (I think I mentioned this as slippage or friction originally), but I think since we're talking about theoretical travel of the wheel, we can ignore friction.

    This isn't a perfect measurement, and you can see from all the comments that even the vendors disagree on how to measure their own machines.

    Thanks!

  • jasonroussy

    I have a nordic track treadmill and have had the console replaced 4 times and it broke again less than a year old it slightly ticks me off, would like a new one or my money back.

  • Dan G

    I was wondering this today. I have the NordicTrack CX 990, with a stride length of 18″.

    If it were a matter of dividing that distance into a mile, then: 1 revolution is 2 strides is 36″, or 1 yard; the track shown on the screen is 440 revolutions, or 440 yards; 4 times around the track is 1760 revolutions, or 1760 yards, or 1 mile.

    But doing 1760 revolutions took me almost 30 minutes, which is much longer than it would take me to run 1 mile; and it said I burned 500 calories, which likewise is much more than running 1 mile would burn.

    On the other hand, the 300 revolutions per 1 mile doesn't work either.

    I notice something in two of the comments here, which compare numbers on the elliptical machines with experience running on actual ground:

    Lisa wrote:
    On machine: 2050 revolutions in 35 minutes
    On ground: 1 mile in 10 minutes
    That calculates to: 585.7 revolutions equivalent to 1 mile

    KevinF wrote:
    On machine: 4400 revolutions in 60 minutes
    On ground: 7.5 miles in 60 minutes
    That calculates to: 586.7 revolutions equivalent to 1 mile

    Notice how close those two figures are? Here's something else I notice. If we divide that 1760 figure by 3, we get 586.7. I don't know why that number should be correct, but the coincidence is notable. And it fits with my own experience today. So I propose: For a machine with an 18″ stride, rounding, 587 revolutions = 1 mile.

  • John Minnihan

    Fantastic deductive reasoning.

    As mentioned a few times, my calcs make sense to me (I used the diameter of the wheel as the basis), but your also make sense.

    I think the key difference is whether we're considering theoretical distance traveled by a bike (and thus the wheel is superior to the stride) or by a human runner (and thus stride is the important factor [x number of strides] ).

    Either approach *makes sense* and continues to be theoretical only. I'm amazed that so many folks have enjoyed this post & that it has generated so much interesting & differing analysis.

  • Eileen

    OH MY GOODNESS!!!! THANK YOU!!!!!!!! This just made everything soooo much easier(and I didn't have to remember any fancy formulas…. JUST KIDDING) This was super helpful.
    I really don't understand why they don't automatically convert that into miles. I actually spoke with a representative and asked if they had a quick formula. They told me there was no possible way to measure distance on an elliptical. I then pointed out that the manual said ever 640 revolutions was 1/4 mile, but never specified the stride length. They couldn't quite answer but by that time I found your super helpful advice. Thanks again!!!

  • Eileen

    OH MY GOODNESS!!!! THANK YOU!!!!!!!! This just made everything soooo much easier(and I didn't have to remember any fancy formulas…. JUST KIDDING) This was super helpful.
    I really don't understand why they don't automatically convert that into miles. I actually spoke with a representative and asked if they had a quick formula. They told me there was no possible way to measure distance on an elliptical. I then pointed out that the manual said ever 640 revolutions was 1/4 mile, but never specified the stride length. They couldn't quite answer but by that time I found your super helpful advice. Thanks again!!!

  • tleernocn1973

    My manual said same thing, but it just seems like alot for just 1/4 mile, ya know? Oh well, in 20 minutes with 15 inch stride, I get about 900 revolutions on my elliptical. Still don't really understand the conversions. I just wish I knew in miles what I was doing on this Nordic Track.