Treadmill Physics: Attaching a Bungee from your Waist to the Wall Behind You

I think the consensus is that running on a good treadmill is only different due to wind resistance. The 1% incline is an attempt to make places equal on the treadmill versus outside, but it changes your stride and muscle recruitment slightly.

Running on a flat treadmill at 10mph should be exactly like running outdoors with a 10mph tailwind. A very weak bungie might approximate outdoor running better than a 1% incline, but im not sure exactly how it should be attached.

A very large fan blowing wind from the front of the treadmill would be the best approximation. That's a pretty substantial fan setup, though. I wouldn't over think it. Just running on the flat treadmill is probably good enough. If you are going to be on the treadmill a lot, mix up the incline just for variety, not to make it "as hard" as running outside.

this sounds like a good idea you should try it

v cool v legal wrote:

this sounds like a good idea you should try it

If the local YMCA got upset about me wearing spikes on their treadmill, I can only imagine what will happen when I start drilling a hole in the wall behind the treadmills to screw in an eye bolt.

v cool v legal said: this sounds like a good idea you should try it

and... you should also set up a video camera to record the moment when you stop running and the bungee cord yanks you backwards off the treadmill.

I think I might pay to see that.

cheers.

I've found that the difference between "running" on a treadmill and real running is similar to the difference between "riding" a stationary bike versus real cycling. You can use the artificial version to build fitness for the real version, but the artificial version works a differently distributed and more isolated group of muscles. With real cycling, being clipped into works more a greater number of muscles in your calves, and a standing climb is something you can't simulate on a stationary bike because it can't rock side-to-side. With real running, your calves have to absorb the impact of varied terrain, and your arms have to more work to cut through air resistance.

jamin wrote:

I've found that the difference between "running" on a treadmill and real running is similar to the difference between "riding" a stationary bike versus real cycling. You can use the artificial version to build fitness for the real version, but the artificial version works a differently distributed and more isolated group of muscles. With real cycling, being clipped into works more a greater number of muscles in your calves, and a standing climb is something you can't simulate on a stationary bike because it can't rock side-to-side. With real running, your calves have to absorb the impact of varied terrain, and your arms have to more work to cut through air resistance.

Interesting take. Prolly a lot of truth to that.

Side question: do you ride much? Have you ever used rollers vs a trainer? Scary as crap, but they force you to use those stabilizer muscles (even more than riding outside) and you finish feeling completely wiped out. (I wonder if the bungee on the treadmill could have the same effect that rollers do for riding? Prolly not as direct a relationship...)

jamin said: your arms have to more work to cut through air resistance.

lol

you've finally explained it. the air resistance on my arms is clearly why I don't run faster. maybe that's why elites wear those compression sleeves, to reduce the air resistance on their arms. can we please start a thread on the diet required to make you lose weight off your arms to reduce the air resistance. are there special exercises I can do to make my arms thinner?

you know Jamin, I think you're on to something.

either that or you're on something.

cheers.

cotton shirt wrote:

jamin said: your arms have to more work to cut through air resistance.

lol

you've finally explained it. the air resistance on my arms is clearly why I don't run faster. maybe that's why elites wear those compression sleeves, to reduce the air resistance on their arms. can we please start a thread on the diet required to make you lose weight off your arms to reduce the air resistance. are there special exercises I can do to make my arms thinner?

you know Jamin, I think you're on to something.

either that or you're on something.

cheers.

Just get on what Chris Froome is on.

Drainthefecesswamp wrote:

I think the consensus is that running on a good treadmill is only different due to wind resistance. The 1% incline is an attempt to make places equal on the treadmill versus outside, but it changes your stride and muscle recruitment slightly.

Running on a flat treadmill at 10mph should be exactly like running outdoors with a 10mph tailwind. A very weak bungie might approximate outdoor running better than a 1% incline, but im not sure exactly how it should be attached.

A very large fan blowing wind from the front of the treadmill would be the best approximation. That's a pretty substantial fan setup, though. I wouldn't over think it. Just running on the flat treadmill is probably good enough. If you are going to be on the treadmill a lot, mix up the incline just for variety, not to make it "as hard" as running outside.

Better option is to bolt the treadmill to the top of a car and have the car drive the speed of the treadmill, will pretty accurately estimate wind resistance

cotton shirt wrote:

jamin said: your arms have to more work to cut through air resistance.

lol

you've finally explained it. the air resistance on my arms is clearly why I don't run faster. maybe that's why elites wear those compression sleeves, to reduce the air resistance on their arms. can we please start a thread on the diet required to make you lose weight off your arms to reduce the air resistance. are there special exercises I can do to make my arms thinner?

you know Jamin, I think you're on to something.

either that or you're on something.

cheers.

What are you talking about?

On a treadmill, all your arms have to do is balance your upper body.

Outside, they have to do the same plus cut through wind.

"My arms are tired" is a common feeling among runners after a difficult race.

jamin wrote:

cotton shirt wrote:

lol

you've finally explained it. the air resistance on my arms is clearly why I don't run faster. maybe that's why elites wear those compression sleeves, to reduce the air resistance on their arms. can we please start a thread on the diet required to make you lose weight off your arms to reduce the air resistance. are there special exercises I can do to make my arms thinner?

you know Jamin, I think you're on to something.

either that or you're on something.

cheers.

What are you talking about?

On a treadmill, all your arms have to do is balance your upper body.

Outside, they have to do the same plus cut through wind.

"My arms are tired" is a common feeling among runners after a difficult race.

You're trolling us, right?

First, we all know there is no wind resistance. How much is that REALLY costing you on your run? The information I can find says it is anywhere from 5 to 10 seconds per mile at 4:30 to 5 minute pace. How many of you are routinely running that fast on the treadmill? As the pace slows, the effect of no wind resistance decreases.

The opposite is true when you calculate the effect of incline on pace. At 5 minutes per mile, 1% incline will cost you 12 seconds. While very close to the upper limit of 10 seconds per mile saved from wind resistance, it is still greater. If you calculate 7 minute pace, the cost of wind resistance is lower (maybe much lower) but raising the incline 1% will cost you 15 seconds per mile. At an easy pace of 8:30 per mile, the cost of wind resistance is said to be negligible but raising the incline 1% now costs you 17 seconds per mile. That easy 8:30 is really being run at 8:13 effort.

The other factor involved that can make a huge difference is heat dissipation. The lack of air movement and high temperatures of some fitness centers can create an environment equivalent to a dewpoint of 70 degrees. At that level, pace will slow by 2% to 3%. For 5 minute pace, that can be 5 to 9 seconds. For 7 minute pace 8 to 13 seconds and for 8:30 pace 10 to 15 seconds. While heat dissipation may affect you very little on shorter runs, it will make a bigger difference the longer you run.

Considering the above, if you are gifted enough to be routinely running 5 minute or faster miles, then raising the incline 1% will give you a close enough effort to running outside on a completely still day on a flat surface or you could just bump up the speed a few seconds and get the benefit of faster turnover.

For the rest of us slowpokes, you can just keep the treadmill at 0 incline and run whatever pace feels right that day and it's going to be pretty close to what you would have done outside running around a flat track.

Of course we know that very few people just go run around a flat track all the time so feel free to hit that incline button all you want and mix in some hills. Just remember that every 1% you increase, it will be 10 to 15 seconds harder for the fast runners and 15 to 20 seconds harder per mile for the slower runners. If you really get ambitious and crank up the incline into the double digits, it will get incrementally harder depending on your pace and when it becomes more efficient to walk rather than run.

Tomorrow I will analyze the difference between running on a flat track with a 7 mph wind at our back, a dirt trail with some roots and rocks at an average incline of 11%, and a descending paved road with a decline of 6%!

Good read. Thanks for the thoughtful reply.

Please don’t ruin your treadmill by gluing rocks and sticks to the belt, though ?

hope this helps........... wrote:

First, we all know there is no wind resistance. How much is that REALLY costing you on your run? The information I can find says it is anywhere from 5 to 10 seconds per mile at 4:30 to 5 minute pace. How many of you are routinely running that fast on the treadmill? As the pace slows, the effect of no wind resistance decreases.

When I looked into it in the past, the effect of no wind resistance was more along the lines of 17-20 seconds per mile, and didn't change that much as the pace slowed through common running speeds. Yes, the effect of wind resistance decreases as pace slows, but 17-20 seconds per mile becomes a smaller percentage of the pace. For instance 17-20 seconds at 4:00 pace is 8%, while 20 seconds at 8:00 pace is 4%. My source was those VDOT calculators with additional factors that you could input. The ones I can find now have removed the wind input though, just having altitude and temperature effects.

The bungees keep the plane from taking off.

As Jarmin pointed out, the biggest problem with a treadmill is the surface is too regular each stride is exactly like the last. There is no variation for camber, uneven surfaces or changing stride to avoid pot holes etc. Also, you are always running in a straight direction, no turning. If you mix in treadmill running with outdoor running then this will probably not be too much of a problem. But if you make the same mistake as me, sign up with a gym for the winter and just run on a treadmill for three months then you will have all sorts of issues when you return to the real world.

Raddison wrote:

As Jarmin pointed out, the biggest problem with a treadmill is the surface is too regular each stride is exactly like the last. There is no variation for camber, uneven surfaces or changing stride to avoid pot holes etc. Also, you are always running in a straight direction, no turning. If you mix in treadmill running with outdoor running then this will probably not be too much of a problem. But if you make the same mistake as me, sign up with a gym for the winter and just run on a treadmill for three months then you will have all sorts of issues when you return to the real world.

Atrophied stabilizer muscles and whatnot?

theJeff wrote:

Raddison wrote:

But if you make the same mistake as me, sign up with a gym for the winter and just run on a treadmill for three months then you will have all sorts of issues when you return to the real world.

Atrophied stabilizer muscles and whatnot?

I have no idea of their names but it was the ankles and hips where I noticed it most. Basically some of the secondary muscles got a free ride for three months. No injuries as such, but I had a dip in performance for the first few weeks back on the road mainly in terms of endurance. I had to reduce the volume while the secondary muscles caught up with the others.

The formula for kinetic energy is 1/2mv^2, which means kinetic energy is cut by a factor of 4 when velocity is cut by a factor of 2. Going from a 4 minute mile to an 8 minute mile cuts the wind resistance by 4x, so we should see the amount of time saved on each mile cut in half when the mile time doubles.