[quote]GDollars37 wrote:
dhuge67 wrote:
Not a runner but I get Army-tested in the 2-mile run. My current time is 12:45. I run 3x a week, 4 at the most, and never for more than 30 minutes.
I thought you were going Marine PLC. Why the change of plans, if you don’t mind my asking?
For me, just starting to get in a running routine (and by just starting, I mean tonight), mile time is probably a bit under 8 min., did a 24 min. 3 mile a few months ago, and that was with only a few weeks of irregular running/jogging under my belt.[/quote]
He was not ready to be a Marine…A little Jar head humor
Aren’t
Ready to be a
Marine
Yet
I don’t agree with the last part. I mean, if you’re not taking steps forward on the treadmill, then what are you doing? I agree more with the slight changes in slope and wind resistance. Plus there’s the often stopping to turn or cross a street when running. I think it’s actually harder to stop for a 5 second pause and then start up again than to continue running.
There’s physics to consider.
How much would gas mileage differ if a car was running on powered rollers as opposed to driving down the freeway?
On a road or track you are carrying a given mass across a surface. On a treadmill, there is NO forward motion of that mass to perpetuate.
[/quote]
I believe it would be largely a question of bioenergetics.
I don’t think physics would be terribly useful because when considering the treadmill runner, in order to develop a useful frame of reference you’d have to consider the treadmill belt to be stationary when the running is moving and thus it would be mechanically equivilent to running over normal ground at equivilent velocities.
I believe it would be largely a question of bioenergetics.
I don’t think physics would be terribly useful because when considering the treadmill runner, in order to develop a useful frame of reference you’d have to consider the treadmill belt to be stationary when the running is moving and thus it would be mechanically equivilent to running over normal ground at equivilent velocities. [/quote]
Does propelling a given mass (you) across a stationary surface not factor in here?
Each step is required to push your mass forward through space. Treadmill running has no such requirements.
You don’t think you’d notice a difference if the track started moving toward you at the exact same speed you were running?
On a track you have to use your muscles to pull your legs back, which drives your body forward, on the treadmil the mill pulls your legs back for you, you just have to bring them forward again.
I’d have to say that the treadmill’s easier to run on - I guess partly because it does half of the work for you. On the road there’s nothing to push you forward like there is on a 'mill. I can easily go for half an hour at a decent pace and incline on the treadmill - it’s a totally different story when it comes to road-running.
I believe it would be largely a question of bioenergetics.
I don’t think physics would be terribly useful because when considering the treadmill runner, in order to develop a useful frame of reference you’d have to consider the treadmill belt to be stationary when the running is moving and thus it would be mechanically equivilent to running over normal ground at equivilent velocities.
Does propelling a given mass (you) across a stationary surface not factor in here?
Each step is required to push your mass forward through space. Treadmill running has no such requirements.
You don’t think you’d notice a difference if the track started moving toward you at the exact same speed you were running?[/quote]
My only point was it’s a more complicated physics problem than you stated because there are multiple frames of reference to consider.
You are correct and something as simple as a respitory calorimeter would demonstrate that quite well.
I believe it would be largely a question of bioenergetics.[/quote]
Yes, the energy it takes to run or walk on level ground involves biomechanical efficiency and is not a simple physics problem, but some simple physics considerations are useful. For example…
this argument is correct, it IS basically equivalent energetically. It’s different in a lot of lesser details - no wind resistance, soft treadmill deck is easy on knees but slows you down, rock steady pace, boring (or not with a TV), no cool air, no concern for footing, etc. But it’s not VERY different.
Well, if there’s no friction, moving at a constant velocity through space costs ZERO energy, so there’s no difference in the power required if you look at the problem in a different frame of reference, like that of the moving treadmill deck. A person doesn’t move at constant velocity, though, so it does take energy. The extra energy to go up an incline you could get from simple physics, at least.
If you tell yourself no effort is required to move on the treadmill, you will shoot off the back, bounce off the gym wall, and embarrass yourself in front of the cardio bunnies.
After the initial shock, you’d find you had to run hard just to stay still.
Anyway, I guess this is sort of a thread hijack. Sorry to contribute to that, I just think it’s kinda interesting.
The backward push from the hamstrings calves and glutes is minimized by the rearward-moving track effectively neutralizing that push, keeping you in one place in space or in other words, exactly matching the treadmills’ speed.
When you run on a hard, stable surface, that push does NOT get neutralized but is transfered rearward through the ground thus propelling you forward.
[quote]derek wrote:
The backward push from the hamstrings calves and glutes is minimized by the rearward-moving track effectively neutralizing that push, keeping you in one place in space or in other words, exactly matching the treadmills’ speed.
When you run on a hard, stable surface, that push does NOT get neutralized but is transfered rearward through the ground thus propelling you forward.
Not the same.[/quote]
Derek,
Sure, it’s different, but not very different. In one case, you push against the Earth’s surface and move relative to it. In the other case you push the treadmill track and move relative to it, and you are required to push an amount that lets you match the treadmill speed. Both pushes are about the same strength, I think. The push against the treadmill is “neutralized”, but you still had to push! That’s a big part of the total energy of running. If it was effortless on a treadmill, people’s treadmill speeds would be MUCH faster than track speeds, not just a little different.
Have you ever been on one of those really long airport terminal moving walkways, like in Phoenix? You step onto it and it feels odd for a second as you match speed. But then you could stand still, walk forward or backwards, whatever and it’s like a normal sidewalk, except your surroundings are whipping by, which is a little disorienting. If it moved at 6 mph and you turned around and ran backwards at 6 mph, you’d stay in the same place in the terminal. It would be like a treadmill. Or you could run forwards and move at 12 mph in the terminal. I think you’d use the same energy either way, except for a little extra to move air out of your way in the 12 mph case.
If that example doesn’t change your thinking on it, we can just scratch our heads and agree to disagree. Or maybe someone who actually knows the answer can chime in. There is no way that runners have not had this discussion a million times.
I agree that it’s different but not VERY different.
I searched the runners forums, about six of them, and they all agree about the treadmill carrying your feet back for you while you must push them back while on a track.
This is a difference and may not seem like a big one but everyone I read commented how they are much more winded/tired from a track run.
And variables such as wind were deemed unimportant on track runs becuase a mild headwind turns into a mild tailwind with every lap.
They also concluded that running on a treadmill was akin to running slightly downhill and to better simulate a track, you’d need to increase the incline somewhat albeit a small amount which I found very interesting.
I’m certainly NOT an expert so I’ll just leave it up to the people that spend several hours each week running on all different surfaces and conditions.
EDIT: Re-reading this, it sounds confrontational. Which is certainly NOT my intention. Sorry if it comes off that way.
[quote]derek wrote:
I agree that it’s different but not VERY different.
I searched the runners forums, about six of them, and they all agree about the treadmill carrying your feet back for you while you must push them back while on a track.
This is a difference and may not seem like a big one but everyone I read commented how they are much more winded/tired from a track run.[/quote]
Ok, I still don’t get this, but I defer to the wisdom of the runners.
[quote]And variables such as wind were deemed unimportant on track runs becuase a mild headwind turns into a mild tailwind with every lap.
They also concluded that running on a treadmill was akin to running slightly downhill and to better simulate a track, you’d need to increase the incline somewhat albeit a small amount which I found very interesting.[/quote]
That is interesting. I recall a runner saying that running on a treadmill at 8 mph would be like running outside in an 8 mph “following wind”.
[quote]I’m certainly NOT an expert so I’ll just leave it up to the people that spend several hours each week running on all different surfaces and conditions.
EDIT: Re-reading this, it sounds confrontational. Which is certainly NOT my intention. Sorry if it comes off that way.[/quote]
It didn’t feel confrontational at all, I agree the opinions of the runners are important, thanks for investigating. Sorry if my posts have seemed confrontational. Just trying to figure it out. I hope I didn’t kill the original purpose of your thread, which was also interesting.
I’ve been running/jogging for about two weeks, but not consistent. My original 1 mile time was 9 minutes. Yesterday my first mile was 8, the second mile was 8:45. Not too bad for weighing 240.
[quote]derek wrote:
The backward push from the hamstrings calves and glutes is minimized by the rearward-moving track effectively neutralizing that push, keeping you in one place in space or in other words, exactly matching the treadmills’ speed.
When you run on a hard, stable surface, that push does NOT get neutralized but is transfered rearward through the ground thus propelling you forward.
Not the same.[/quote]
This fails to take into account that when you are running on a hard stable surface, that your body has forward momentum which conserves energy so as to maintain your speed. I dont know all the physics behind it, but saying the “push is neutralized but is transfered rearward through the ground thus propelling you forward” does not take into account that you have forward momentum which will propel you forward with less energy expended than if you were at a complete stop. The treadmill does not have forward momentum; so one could say that the treadmill expends more energy; but i suspicion both are about the same as far as energy expenditure.
The one thing i will say about the treadmill is that the treadmill is a lot more difficult for me because it seems more of a grind; where running outdoors in the fresh air with scenery is a lot more pleasant making it easier for me to run outside than on a treadmill…