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lym
12-05-2008, 06:16 AM
Hi can anyone help me with this. I bought a elliptical and the distance is in revolutions. I need to know how many revolutions equal a mile. I was told it was 300-350 revolutions to a mile. Is this correct?

Robert Fogt
12-05-2008, 06:37 PM
It probably differs between manufacturers, and you'd have to contact them for that information.

1 mile = 5280 feet

If 1 revolution was 2 steps (ie right foot then left foot) and your step is 2 foot long, then:

5280 feet / 2 feet = 2640 steps / 2 = 1320 revolutions

If you can measure how long each stride is, and determine for sure how many steps/strides in each revolution, then you could calculate fairly accurately.

That wouldnt work for exercise bikes, just elliptical machines.

lym
12-06-2008, 04:50 AM
Thanks for the help so you think 1 mile is 1320 revolutions? Wow that is different from what Welso said they claimed 300-350 revolutions = 1 mile. Here is more info I have a Weslo Momentum 620 the stride is '13 and when I use it once I go round once right and left foot the revolution changes to 1.

It probably differs between manufacturers, and you'd have to contact them for that information.

1 mile = 5280 feet

If 1 revolution was 2 steps (ie right foot then left foot) and your step is 2 foot long, then:

5280 feet / 2 feet = 2640 steps / 2 = 1320 revolutions

If you can measure how long each stride is, and determine for sure how many steps/strides in each revolution, then you could calculate fairly accurately.

That wouldnt work for exercise bikes, just elliptical machines.

JohnS
12-06-2008, 07:00 AM
Lym,

You have to analyze the horizontal motion of the pedal. In one revolution, it returns to where it was (it corresponds to a left stride and a right stride). Your machine's stride is specified as 13" but you could measure it. Place a newspaper under machine (to mark on) rotate wheel slowly, and place a mark on paper vertically below the forward and rearward points of travel ot the toe tip (or any feature of the pedal) and measure the stride.

A mile is 5280 feet or 63360 inches. There are 2 strides in a revolution, so divide 31680 inches by the stride 13 inch/stride. I think your machine is 2437 rev per mile. Other machines have longer strides, 18" which would be 1760 rev per mile.

In normal walking, most people have a stride (one sided) of 30" or a pace (left and right) of 60". I'm tall, have a natural stride of 36" so any of these machines would force me to take "baby steps."

The difference between this figure and the 300 rev/mile claim may be exertion. The elliptical may require you to overcome resistance over more of the range of motion or overcome greater resistance than normal walking would require. If they have data to back it up, this "work equivalence" point of view would also have merit. We have directly related the horizontal movement to walking distance, but ignored effort.

Robert Fogt
12-06-2008, 07:02 AM
I would go by what the manufacture claims.

But if I had to figure it out:

5280 feet / 12 = 63360 inches
63360 inches / (13 inches * 2) = 2436.92 revolutions

13 inches * 2 = 26 inches * 300 revolutions = 7800 inches = 650 feet = 0.12 miles

But 13 inches seems like a very very short stride, like baby steps. That probably is a typo.

Robert Fogt
12-06-2008, 07:03 AM
Wow I type too slow. ;)

JohnS
12-06-2008, 07:12 AM
Great minds think alike. :)

The 13" claim troubled me, so I looked at several machines. 13", 15", and 18" all seem common. It is limited by the diameter of the wheel (at the point the linkage is attached). The pictures would appear to bear out the claim (as well as I can judge. All are basically four-bar linkages which convert rotary and reciprocating motion.

For me, they are baby steps and I'm sticking to my NordicTrack cross country sky machine.

lym
12-06-2008, 08:28 AM
Now I am really confused. Seems like the number keeps going up.
Lym,

You have to analyze the horizontal motion of the pedal. In one revolution, it returns to where it was (it corresponds to a left stride and a right stride). Your machine's stride is specified as 13" but you could measure it. Place a newspaper under machine (to mark on) rotate wheel slowly, and place a mark on paper vertically below the forward and rearward points of travel ot the toe tip (or any feature of the pedal) and measure the stride.

A mile is 5280 feet or 63360 inches. There are 2 strides in a revolution, so divide 31680 inches by the stride 13 inch/stride. I think your machine is 2437 rev per mile. Other machines have longer strides, 18" which would be 1760 rev per mile.

In normal walking, most people have a stride (one sided) of 30" or a pace (left and right) of 60". I'm tall, have a natural stride of 36" so any of these machines would force me to take "baby steps."

The difference between this figure and the 300 rev/mile claim may be exertion. The elliptical may require you to overcome resistance over more of the range of motion or overcome greater resistance than normal walking would require. If they have data to back it up, this "work equivalence" point of view would also have merit. We have directly related the horizontal movement to walking distance, but ignored effort.

Fletch
09-12-2009, 09:26 AM
Well, quite honestly there is not a direct conversion from revolutions to miles. And that's why most manufacturers give you distance in revolutions instead of distance in miles. It really depends on whether you want "actual" miles or "work equivalent" miles.

Most manufacturers will give you the stride length in the owner's manual. For example, the stride length on my elliptical is 18". And, 2 strides is equal to one revolution. If you don't have the owner's manual you can simply take a tape measure and determine how far one side of the elliptical travels from its furthest point of forward motion to its furthest point of rearward motion. Mulitply that by 2 and you have the total distance travelled for one revolution. This is the "actual" distance travelled.

The reason that most manufacturers give you revolutions is that the distance the wheel travels through one revolution is typically further than the stride distance. For example, if the wheel on your elliptical has a 20" diameter (typical for many Nordic Trac ellipticals), the wheel travels the circumference of the wheel through one revolution or approximately 62.83 inches (5.236 feet).

Circumference = 20" (pi) or 20" (3.14159) = 62.83 inches (divide by 12 inches/foot and you get 5.236 feet)

Realize that through the entire range of motion of the wheel on an elliptical part of the motion translates to up and down motion and not forward motion. However, you still have to expend energy in the form of work to move the wheel through that entire range of motion. So, you've actually done more work in one revolution than just the actual distance travelled by your stride length.

Using the example of my own elliptical, while the "actual" distance travelled for one revolution is 36 inches or 3 feet, you have in fact done work equivalent to travelling 5.236 feet by moving the wheel through one revolution (that's why I refered to it as "work equivalent" miles). Since there are 5280 feet in one mile, I would have to do 1760 revolutions to travel the actual distance of one mile. However, you do the equivalent work of walking one mile in 1008 revolutions (1008 revolutions x 5.236 feet/revolution = 5278 feet). Hope this isn't too confusing.

So, while converting revolutions to miles is not like comparing apples to oranges, it is akin to comparing MacIntosh apples to Red Delicious apples.

BTW, I can tell you from experience that I expend more energy putting 2.5 "work equivalent" miles on my elliptical than I do walking 2.5 actual miles through my very hilly neighborhood.

Hope this helps.

Unregistered
11-22-2009, 05:52 PM
Well, quite honestly there is not a direct conversion from revolutions to miles. And that's why most manufacturers give you distance in revolutions instead of distance in miles. It really depends on whether you want "actual" miles or "work equivalent" miles.

Most manufacturers will give you the stride length in the owner's manual. For example, the stride length on my elliptical is 18". And, 2 strides is equal to one revolution. If you don't have the owner's manual you can simply take a tape measure and determine how far one side of the elliptical travels from its furthest point of forward motion to its furthest point of rearward motion. Mulitply that by 2 and you have the total distance travelled for one revolution. This is the "actual" distance travelled.

The reason that most manufacturers give you revolutions is that the distance the wheel travels through one revolution is typically further than the stride distance. For example, if the wheel on your elliptical has a 20" diameter (typical for many Nordic Trac ellipticals), the wheel travels the circumference of the wheel through one revolution or approximately 62.83 inches (5.236 feet).

Circumference = 20" (pi) or 20" (3.14159) = 62.83 inches (divide by 12 inches/foot and you get 5.236 feet)

Realize that through the entire range of motion of the wheel on an elliptical part of the motion translates to up and down motion and not forward motion. However, you still have to expend energy in the form of work to move the wheel through that entire range of motion. So, you've actually done more work in one revolution than just the actual distance travelled by your stride length.

Using the example of my own elliptical, while the "actual" distance travelled for one revolution is 36 inches or 3 feet, you have in fact done work equivalent to travelling 5.236 feet by moving the wheel through one revolution (that's why I refered to it as "work equivalent" miles). Since there are 5280 feet in one mile, I would have to do 1760 revolutions to travel the actual distance of one mile. However, you do the equivalent work of walking one mile in 1008 revolutions (1008 revolutions x 5.236 feet/revolution = 5278 feet). Hope this isn't too confusing.

So, while converting revolutions to miles is not like comparing apples to oranges, it is akin to comparing MacIntosh apples to Red Delicious apples.

BTW, I can tell you from experience that I expend more energy putting 2.5 "work equivalent" miles on my elliptical than I do walking 2.5 actual miles through my very hilly neighborhood.

Hope this helps.

Fletch, love your explanation. Tell me more, teacher. My elliptical (ProForm Quick Burn Spacesaver) also has an 18" stride, the wheel is not visible in the plastic housing, and I have 10 levels of difficulty (resistance). Assuming my wheel is the same as yours, any chance you know how to calculate the different settings into the equation? I just finished a jaunt with these stats: Level 3, 31 minutes, Distance 1896, Calories burned 465, carbs burned 81. Thanks! Robin

Unregistered
08-18-2010, 05:05 AM
I just finished doing a distance of 2173 in 40 minutes and burned 736 calories according to my eliptical. The stride is adjustable, but is set at 18 in.
I wear a heart rate monitor and keep my heart rate average between 140-150. today the average was 142, this mornitor tells me I only burned 369 calories. the heart rate monitor is set up with my age, weight, height, etc.
Something tells me that neither of these devices are accurate. I am thinking that the heart rate monitor is below what is actually being burned for calories and the eliptical is higher than what I actually burned.
not sure though....this is interesting what the distance would convert to because I am thinking since I usually run 2.5 that the distance 2173 is at least 2.5 miles...probably more like 3 miles...

Unregistered
01-20-2012, 04:53 AM
I just did a crazy thing and contacted Pro Form and asked them. The answer is that for the 18" stride there are 1760 revolutions per mile.

Unregistered
02-02-2012, 08:38 PM
So basically from the most recent post, with the phone call to the actual company, an 18" stride converts basically to 1 yard/ revolution. which would make the 1760 "yards" a mile. Good to know, because I was just looking this up after trying to keep in shape on my wife's elliptical, and in 30 minutes the display said I burned just over 500 calories, and did 2010 revolutions. Thanks for the help folks.. :)

Unregistered
04-11-2012, 01:02 PM
I don't even know when this conversation took pace of I have been looking for this information for a while now and I find this post very helpful. My elliptical has 18" stride length also so using your calculation is my typical workout is about abit more than 3 miles per workout. But when I go to gym with the type of elliptical that shows the miles for a siilar workout it says that I do between 4 and 5 miles depending on the intensity of the partcular day. I find this curious:0

Unregistered
06-26-2012, 07:50 PM
it probably differs between manufacturers, and you'd have to contact them for that information.

1 mile = 5280 feet

if 1 revolution was 2 steps (ie right foot then left foot) and your step is 2 foot long, then:

5280 feet / 2 feet = 2640 steps / 2 = 1320 revolutions

if you can measure how long each stride is, and determine for sure how many steps/strides in each revolution, then you could calculate fairly accurately.

That wouldnt work for exercise bikes, just elliptical machines.

very nice.. My problem only is the linear vel. Because the given on the problem are in revolution/ sec. How can i convert this revolution/sec to miles/sec??

Milkwoman
07-26-2012, 07:25 PM
The formula posted here is incorrect. The only reason I say this is because when I worked out at a gym while on vacation in January, the Lifefitness elliptical there shows miles, steps per minute, etc. and my Nike+ device, which I connect to the machine saves this information. So, looking back, it shows that in one workout, for example, I did 8.2 miles in 67 minutes.

Back at home, I use a older Pro-form elliptical to which I cannot connect Nike+, but I do the SAME type of workout (same intensity, same steps per minute, etc.). If I use the formula posted here, I calculate only doing 5.6875 miles. So, something is definitely wrong with the math.

I found a site that used the following calculation and it gets me closer to what the Lifefitness elliptical and Nike+ recorded.

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. Multiply your result by 2 to get the diameter and then calculate the circumference (C=Pi x Dia).

Next, to calculate the miles per revolution you first need to convert C, which is in inches, to feet (divide C by 12). The resulting number is how many feet you have travelled in one complete turn of the flywheel (a revolution).

How many equal a mile? Well, there is 5280 feet in one mile so, divide 5280 by the feet travelled in one revolution to yield how many revolutions needed to go one mile.

Here is the calculation using the values I measureded on my home elliptical:

Diameter=18 inches
Circumference (C)=56.5486677 inches
C/12=4.71238898 feet
5280/4.71238898= 1120.4508 revolutions needed to travel one mile

My machine at home records distance. In a recent 67 minute workout, the machine recorded 5,005. I need to multiply this number by two since I need to complete two full revolutions for each count.

5005 x 2 = 10010

10010/1120.4508= 8.9 miles

This number makes sense to me since my pace has improved since the workout at the gym in January.

Mrs X
07-27-2012, 01:41 PM
My machine at home records distance. In a recent 67 minute workout, the machine recorded 5,005. I need to multiply this number by two since I need to complete two full revolutions for each count.

5005 x 2 = 10010

10010/1120.4508= 8.9 miles

This number makes sense to me since my pace has improved since the workout at the gym in January.

If you are indeed walking, this is pretty close to the olympic qualifying level. Just keep training for a couple more miles at that pace, and we'll see you there in 2016! :)

http://en.wikipedia.org/wiki/Racewalking

Unregistered
07-27-2012, 06:01 PM
I have a PF900 and was perusing the internetwebs for discussion on converting the RPM to linear miles. I think the r2 x pi x 2 is likely the most accurate calc. One point to consider is that 'running' on an elliptical is basically like upright bicycling in that our feet are turning a wheel... now on my bike computer I need to enter the wheel diameter into the computer and it tells me the mileage for each trip, regardless of how much pedaling it took to get there (RPM equiv) or what gear I was in (work load)...

Mrs X
07-28-2012, 12:31 PM
I have a PF900 and was perusing the internetwebs for discussion on converting the RPM to linear miles. I think the r2 x pi x 2 is likely the most accurate calc. One point to consider is that 'running' on an elliptical is basically like upright bicycling in that our feet are turning a wheel... now on my bike computer I need to enter the wheel diameter into the computer and it tells me the mileage for each trip, regardless of how much pedaling it took to get there (RPM equiv) or what gear I was in (work load)...

The problem with this is that the distance you are walking or running is not the same distance as the flywheel travels, unless the tread revolution is exactly the same size as the circumference of the wheel. (Unlikely). The wheel is likely to turn a lot more often than the track on the treadmill.

Milkwoman
07-30-2012, 09:06 AM
[QUOTE=Mrs X;87777]If you are indeed walking, this is pretty close to the olympic qualifying level. Just keep training for a couple more miles at that pace, and we'll see you there in 2016! :)

That's funny. However, I don't "walk" on my elliptical...my pace is akin to running and I average a 7.75 - 7.90 minute mile. My elliptical has articulated petals, meaning they go up and down, allowing me a more natural gait. I don't keep my feet flat on the petals (as they would go numb after a while) but rather, keep them moving such that I am basically stepping as if I were actually running on the street.

(BTW...I also do HIIT training on the machine so combined with this pace are a series of tough resistance levels. Yeah, I'm a maniac. :-) )

Now, whether or not I am actually travelling the mileage I am calculating? That I am not 100% sure. It may be more "equivalent" miles, meaning, if I were indeed running on the street at this same pace, this is the equivalent distance I'd be travelling. I do know that my workouts are very intense, my heart rate fluctuates in-between cardio pace and fat-burning pace (depending upon where I am in the HIIT) and over the course of a year of doing this, I am in the best shape of my life, both heart-wise and muscle tone-wise.

slick
09-21-2012, 01:54 PM
so are the numbers on the bottom of the screen in revolutions