Burning Question # 981:-


Treadmills are touted as the ultimate cardio machine. Both for burning calories and conditioning.

Elipticals are a little lower in the pecking order.

But a treadmill is motorized. Therefore , when it is on, the hamstrings are not taxed too heavily because you do not use them much as the belt is creating your forward motion whether you are walking or running on it. The musculature required is that which moves each leg ahead of the belt. As the leg contacts the belt, the belt pulls it back.

However.....:doh: :mad: :eek: :o .....on an Eliptical, all leg muscles are required continually to activate the machine. So, the hams are involved much more as they do more work, per capita, than a tread mill allowing for the fact that the Eliptical is NOT electrically powered.

So,logically, it would seem that an eliptical, (or Nordic-type cross country ski-machine) would burn more calories per given parameters because the leg muscles have to work harder on either of those machines than they do on a treadmill.

True, you can run on a treadmill...which might mean greater quad activation. But the trade-off is that the Eliptical has higher resistance settings, thereby making the quads work way harder overall.

You do not run on a treadmill the same way you would on open ground by virtue of the fact that the belt moves underneath you whereas hard ground does not. Therefore more muscle is required to propel you across a stationary surface.

You might get a bit of Ham involvement if you have an incline on your treadmill. But it still won't be the same leg involvement as open ground.

So.....keeping all this in mind, wouldn't the eliptical or ski-machine be a better choice overall for total leg muscle involvement than the treadmill?

:rolleyes:

Treadmills are touted as the ultimate cardio machine.

By who? I've read they're nearly equal, with the elliptical having the low impact advantage as well as a lower perception of effort for the same amount of output (due probably to the lack of impact). Plus, the elliptical allows for arm use and is easier to do in reverse (using different dominant muscles) without falling :)

If I was going to buy something, it would be the elliptical. Treadmills have their value, especially if you are a runner anyway, my knees just don't like me to run too regularly.

Give me my Norditrack Elliptical any day! I get one heck of a workout. The imact on my joints is virtually zero.

By who? I've read they're nearly equal

Yeah - I think the only advantage treadmills have is they've existed longer, so anyone who hasn't been in a gym in the past 10 years probably couldn't tell you what an elliptical is. I agree with everything else MB says. :D

Burning Question # 981:-

But a treadmill is motorized. Therefore , when it is on, the hamstrings are not taxed too heavily because you do not use them much as the belt is creating your forward motion whether you are walking or running on it. The musculature required is that which moves each leg ahead of the belt. As the leg contacts the belt, the belt pulls it back.

You do not run on a treadmill the same way you would on open ground by virtue of the fact that the belt moves underneath you whereas hard ground does not. Therefore more muscle is required to propel you across a stationary surface.

You might get a bit of Ham involvement if you have an incline on your treadmill. But it still won't be the same leg involvement as open ground.



This is not true. Any high-school physics textbook would explain Newton's laws of motion, one of which is that "Every action has an opposite and equal reaction." Essentially this means that all motion is relative - so whether you're running on a moving belt, or the still ground, your body knows no difference.

Example: If you were on a "people mover" (you know, those conveyor belts) at the airport and ran for 5 seconds in one direction and later ran 5 seconds in the opposite direction they would be equally good workouts that your body would not be able to differentiate. And if your eyes were closed you wouldn't even know if you were running in the same direction the belt was moving or against it.

On a "people mover' belt, the body and the belt are both moving...

so force is required to move you ahead of the belt

in the same way that if you are on a jet, seated, travelling at 500 miles an hour, you will use the same forces to walk towards the front of the jet as you would if you were on the ground, with no noticeable effect.

But the treadmill belt is moving underneath you. If you do nothing you will travel backwards.

To stay in place you have to continually put one leg in front of the other. But as soon as your leg contacts the belt, the belt will move it backwards even if you apply NO force.

There is no force involved to propel yourself ahead (as there
would be on hard ground)

You are merely keeping place. The force required to do this is not the same as if you were propelling yourself forward on hard ground.

Therfore the hams and certain other muscles would not work as hard as if you were on the ground (or on an eliptical, which, by it's un-motorized design forces those muscles to work inorder to activate the machine completely).

Newton owned neither a treadmill or an eliptical but I hear he was good with apples...:cool:

On a "people mover' belt, the body and the belt are both moving...

so force is required to move you ahead of the belt

in the same way that if you are on a jet, seated, travelling at 500 miles an hour, you will use the same forces to walk towards the front of the jet as you would if you were on the ground, with no noticeable effect.

But the treadmill belt is moving underneath you. If you do nothing you will travel backwards.

To stay in place you have to continually put one leg in front of the other. But as soon as your leg contacts the belt, the belt will move it backwards even if you apply NO force.

There is no force involved to propel yourself ahead (as there
would be on hard ground)

You are merely keeping place. The force required to do this is not the same as if you were propelling yourself forward on hard ground.

Therfore the hams and certain other muscles would not work as hard as if you were on the ground (or on an eliptical, which, by it's un-motorized design forces those muscles to work inorder to activate the machine completely).

Newton owned neither a treadmill or an eliptical but I hear he was good with apples...:cool:

The people mover is nothing but a giant treadmill so if you believe what I said applies to that, you must believe it is true for the treadmill too.

Let me point out a major flaw in your argument: 1st you state that if you apply no force on a treadmill you will move backwards. That is true and is exactly my point. Later you contradict yourself and state that there is no force involved to propel yourself ahead on the treadmill. Obviously both statements cannot be true.

I assume that your response would include something to the effect that the force you are applying is only pushing you up to allow the belt to move underneath you. Let me assure you that if you had a treadmill big enough (or were on a people mover - facing backward of course) and you jumped straight up you would land behind the spot where you jumped (but you would land on the same spot on the belt).

Likewise if you apply no force on the ground you would move nowhere. If you jumped up you would land on the same spot you jumped from. And if you run forward you will move forward.

The only difference between a treadmill and the ground is that they have different "bouncing" characteristics. ie. Running on concrete would have no bounce, a rubber track may have a little, and different treadmills, I assume, would have different degrees of bounce. Oh - and a treadmill only allows you run in a straight line.

When an athlete runs on the track, on roads or on firm ground, their legs create propulsive forces which accelerate their centre of mass and drive it forward. The athlete's centre of mass is decelerated during each recovery (early-stance) phase of the gait cycle, only to be accelerated forwards again as propulsive forces are created by the stance leg. As they continue to run, centre of mass is accelerated and decelerated over and over again as it moves steadily forwards.

When the same athlete runs on a treadmill, centre of mass is static (at least in the forwards-backwards plane). There is no forward progress; instead, the running surface 'disappears' behind the athlete. In fact, the treadmill belt moves the athlete's legs and feet under and behind her centre of mass and, to preserve stability, their key task is to move the support leg back in front of the centre of mass in time for the impact with the treadmill belt. The key function of the leg muscles during treadmill running is not to produce propulsive forces but to re-position the legs so as to keep the centre of mass stable.
Because of these major and fundamental differences, some experts have argued that treadmill training is unspecific to 'real running' and should be avoided by athletes who want to improve their running abilities on the ground. The neuromuscular patterns involved in treadmill running are so different from road, track or cross-country running, they argue, that improvements in economy and efficiency are not possible. Some go so far as to contend that treadmill training may actually impair running economy on regular surfaces.

in laymans terms, propelling ones self forward (over and over to overcome the deceleration of your mass) requires more energy than moving your feet, one in front of the other, to keep up pace with the treadmill (where there is no deceleration of your mass). my cardio used to consist of treadmill training, until i discovered that 4 miles running on flat ground was giving me an entirely more rigorous workout than running 4 miles on the treadmill. i run exclusively outdoors now.

i will concede that a treadmill offers softer impact than most outdoor surfaces. additionally some people dont want to deal with the elements, traffic, etc...

a treadmill is better than nothing, for sure, but propelling yourself along the ground is the best bang for your buck.

I don't know of anyone who would claim that a treadmill offers a better workout than an elliptical.

I have an elliptical myself, and while I agree that it offers a more rigorous workout with less perceived effort, there are times that I would prefer a treadmill.

On an elliptical, as I get tired, I naturally start to move my legs more slowly, cheating myself out of a good workout. My speeds and distances vary drastically based on what time of day I do it, my mood, the music I'm listening to or video that I'm watching.

On a treadmill I must sustain my preprogrammed speed if I don't want to fall over. I like the fact that I can set it up to take me through an alternating program of flat terrain, hills, slow and fast pace. Unless I manually change the settings in the middle of the workout, I have no choice but to keep up: built in motivation.

For someone that likes some encouragement to push harder, I would recommend a treadmill over an elliptical.

Good points guava! :tucool:

I get alot better workout on a treadmill personally. Throw that sucker on 8.0mph with a %8 incline for a few 30s-45s intervals and tell me which is better.

in laymans terms, propelling ones self forward (over and over to overcome the deceleration of your mass) requires more energy than moving your feet, one in front of the other, to keep up pace with the treadmill (where there is no deceleration of your mass). my cardio used to consist of treadmill training, until i discovered that 4 miles running on flat ground was giving me an entirely more rigorous workout than running 4 miles on the treadmill. i run exclusively outdoors now.

i will concede that a treadmill offers softer impact than most outdoor surfaces. additionally some people dont want to deal with the elements, traffic, etc...

a treadmill is better than nothing, for sure, but propelling yourself along the ground is the best bang for your buck.

roxy1, You didn't site the source of your quote, but frankly whoever wrote that (especially if it was a publicly distributed document) was an idiot. And I wouldn't be surprised if it was from "Runner's World" or something similar. (No knock to Runner's World, just the masses of morons out there in the world - and I think everyone can agree with me that there's a lot of them.)

I do agree with you that I get better workouts on the ground than on the treadmill, but the reason (at least for me) is simple. On the gound I can continually push myself; on a treadmill I'm stuck at a preset speed and it's impossible to keep the machine moving at my optimum speed since it would require fine adjustments every few seconds. And maybe part of it is that a treadmill is bouncier than the ground, though I don't know if that's true.

I won't keep arguing the physics of this, but let me reiterate one last time: 1. For every force there is an opposite (and equal) force. 2. All motion is relative. 3. Therefore, all things being equal, running on a treadmill is no different from running on the ground.

I can understand somebody having a hard time and not understanding this at first - much of physics can be counter-intuitive, but people insisting that blatantly wrong info is fact is one of my pet-peeves and so to save myself grief I will try to avoid this thread from now on.

For those of you who post here to say I'm wrong, know you do so at the risk of making yourself look like a fool to the world. Everything I'm saying is based on principals proven by Newton about 320 years ago. For the rest of us, we will continue to land in the same spot we jump from despite Earth's surface spinning at nearly 1000 miles an hour.

If anyone has any question or thinks there is a flaw in my reasoning I invite you to ask/discuss. But please don't insist something is true when it is not.

I do apologize if I seem defensive, but I find physics fascinating and as I stated, it peeves me to see people who misunderstand something preach it as gospel.

P.S. I also agree that propelling yourself along the ground is the best bang for your buck, but canada makes a nice point above too.

roxy1, You didn't site the source of your quote, but frankly whoever wrote that (especially if it was a publicly distributed document) was an idiot.

For those of you who post here to say I'm wrong, know you do so at the risk of making yourself look like a fool to the world. Everything I'm saying is based on principals proven by Newton about 320 years ago. For the rest of us, we will continue to land in the same spot we jump from despite Earth's surface spinning at nearly 1000 miles an hour.

If anyone has any question or thinks there is a flaw in my reasoning I invite you to ask/discuss. But please don't insist something is true when it is not.

I do apologize if I seem defensive, but I find physics fascinating and as I stated, it peeves me to see people who misunderstand something preach it as gospel.
If people misunderstand your position, perhaps you could explain it more clearly instead of resorting to name calling.

I will brave the risk of making myself look like a fool to the world.

Initially, I thought your position seemed the most logical, but after thinking about roxy1's post, that one made sense to me too. They don't completely contradict each other.

While on the elliptical, your foot is being carried backward by the conveyor for part of your workout, giving you a slight rest in the "recovery" portion of the step, which is not present while walking on flat terrain. That sounds like it would probably be less work.

after thinking about roxy1's post, that one made sense to me too. They don't completely contradict each other.


roxy1's post makes the most sense to me too. You do not need any propulsive force to "walk" on a treadmill. You can simply allow the treadmill to pull your foot back while you lean forward, and then you simply catch yourself with your other foot. The treadmill is doing the propulsion for you. This would also be true on a "people mover" if one were to walk against the direction of it while remaining stationary relative to the rest of one's surroundings.

That said, I do believe that a treadmill can provide an excellent workout.

roxy1's post makes the most sense to me too. You do not need any propulsive force to "walk" on a treadmill. You can simply allow the treadmill to pull your foot back while you lean forward, and then you simply catch yourself with your other foot. The treadmill is doing the propulsion for you. This would also be true on a "people mover" if one were to walk against the direction of it while remaining stationary relative to the rest of one's surroundings.

That said, I do believe that a treadmill can provide an excellent workout.

Err...if you're RUNNING this isn't possible, for obvious reasons. Seriously, go try it. I suppose you could just pick up your knee and extend your leg, and then fall forward, but this would just be foolish and inefficient. Besides, it might be more difficult than actually running. Additionally, you could do this just as quickly on flat ground as on a moving treadmill belt if you think about it.

You really do need propulsive force...when you're running (or doing normal walking), you DO propel your body forward. The only difference is that the work you do doesn't result in you moving forward because it's cancelled out by the backward motion of the belt.

Think about it, if the belt is moving backward, and you are not, you MUST be propelling yourself forward. Period.

_________________________

All these questions are kind of vague anyway.

How do you define the "best" equipment anyway? Hevy, yes, obviously a ski machine will exhaust the leg muscles quicker, but so will heavy squats, to a much greater extension.

And then, if you're talking about cardio for fat loss, you have to question whether this is even the most efficient fat loss method. Do the calories burned in a 45 minute treadmill or elliptical session REALLY match the calories burned in an intense 45 minute weight workout when you include the increase in metabolic rate over the next hours?

It all depends on what you want it for...treadmills are great for runners, ellipticals are great if you want low impact. Both give you a cardiovascular workout and burn calories.

One more thing - Where did you hear that running on a treadmill wouldn't use the hamstrings? I don't really think it's much different. I know it sure doesn't feel much different, at least mechanically, other than differences that are caused by other factors, like wind resistance or hills or something.

^^^^I do understand what you're saying, it's probably SLIGHTLY different, because your foot does stay on the ground for a tiny amount of time, so yeah, it's pulled back a little bit, but you still do MOST of the work, and I don't think it makes that much of a difference unless you have an awkward running stride in which you're foot is in contact with the ground for too long.

roxy1, You didn't site the source of your quote

these quotes were taken from a 1998 Penn State study. the following references were cited:

References
(1) Medicine and Science in Sports and Exercise, vol 12(4), pp 257-261, 1980
(2) Journal of Physiology, vol 207, pp 823-835, 1970
(3) Energy Cost of Treadmill Walking Compared to Road Walking, Natick QM Research and Development Laboratory, US Office of the Quartermaster General, 1953
(4) Medicine and Science in Sports, vol 4(4), pp 233-240, 1972
(5) Medicine and Science in Sports, vol 8(2), pp 84-87, 1976
(6) Medicine and Science in Sports and Exercise, vol 15(6), pp 478-485, 1983
(7) Science, vol 275, pp 1113-1115, 1997

another factor making outdoors running more difficult is the fact that you are battling wind resistance whereas with a treadmill there is really no significant wind resistance to overcome.

energy is required to propel a decelerating object. this is a common tenet of physics.

you stated: "Therefore, all things being equal, running on a treadmill is no different from running on the ground."

all thing are not equal on a treadmill. because the ground is moving underneath your feet, your mass is not decelerating as it is running on the ground.

sorry folks, i know this thread was more related to treadmill vs elliptical.

Err...if you're RUNNING this isn't possible, for obvious reasons. Seriously, go try it. I suppose you could just pick up your knee and extend your leg, and then fall forward, but this would just be foolish and inefficient.

Well, I wasn't suggesting that people walk in a Frankenstein-like manner while on the treadmill ... The description was mainly aimed at illustrating how the treadmill is essentially providing the propulsive force. When you run on solid ground, you not only propel yourself forward, but you also propel yourself upward off of the ground. On a treadmill, you would still be required to propel yourself upward -- so in this respect, running on the treadmill is like running on stationary ground. However, once your lead foot hits the treadmill and moves backward, you don't have to apply the same level of backward (propulsive) force that you would on stationary ground.

sorry folks, i know this thread was more related to treadmill vs elliptical.

Yeah, but this is an interesting discussion. I'd never really thought about differences on a treadmill versus solid ground until it was brought up in this thread.

Hello,

I purposely choose a device that does not tax my muscles to much (that's what we lift weights for). I have had them all and always go back to the tread mill. I just bought a new one with power incline and it will make your tongue hang out.
The best for loosing weight for me is the stair-master but after using it for several months I discovered I was loosing leg strength from to much work.

i certainly did not mean to put down treadmills, ellipticals, etc...i think the ability to program a specific workout can be very motivating, as someone mentioned earlier. ive always enjoyed rowing machines, but the good ones seem awfully expensive.

So.....keeping all this in mind, wouldn't the eliptical or ski-machine be a better choice overall for total leg muscle involvement than the treadmill?

A lot of people can burn a lot more Calories on an elliptical than a treadmill. This is because you can go faster against more resistance on the elliptical. I go for my lactate threshold tests on an elliptical for this reason.

But if you really want to burn Calories, screw the machines and do barbell bench step-ups. You can get a lot more resistance than on the elliptical because you are pushing the weight up, as opposed to trying to push down (where you are limited to your weight). Get a nice high bench, put a goodly fraction (like 75%) of your bodyweight on there, and it's time for Calorie conflagration.

ive always enjoyed rowing machines, but the good ones seem awfully expensive.

I think you can get a Concept 2 model D new for $750. That's a fine rowing machine - club quality.

Sorry to post here again when I don't have much to say about treadmills vs. elipticals, but I just wanted to make a couple last comments.

If people misunderstand your position, perhaps you could explain it more clearly instead of resorting to name calling.

I did not mean to offend anyone by "name-calling," but as I suspected the paper roxy1 sited was from an assumably trustworthy source, in this case Penn State University. For the author of such a research effort to have such a gross misunderstanding of physics and the world around them - and for it to get published - is a shame. But alas, that is the world we live in.

By the way, when arguing/discussing things I would usually say "in my opinion," but I can't here because physics is a matter of fact. That being said, the various responses here show what a great misunderstanding people have about the world around them. I encourage all of you who may have an interest to enroll in an introductory physics class - in high scool, at the local junior college, at a 4-your school, whatever. Some things would really blow your mind - and my posts here would be vindicated.

I think Andrew summed it up best:

Think about it, if the belt is moving backward, and you are not, you MUST be propelling yourself forward. Period.
Oh no Andrew, what's this:

I do understand what you're saying, it's probably SLIGHTLY different, because your foot does stay on the ground for a tiny amount of time, so yeah, it's pulled back a little bit, but you still do MOST of the workWhy Andrew?! :cry: Why?! :cry:It is NO different, and your foot is not pulled back by the belt AT ALL - at least no more than the ground pulls back on your foot when you're running outside.

If anyone wants to start a "Physics of Working Out" post I would gladly post to it, but I'll try to refrain from straying off topic here in the future. My only concern is a post like that could spread around a lot of bad information to a lot of people.

I think I'll end this one with a quote from Einstein:

"Great spirits have always encountered violent opposition from mediocre minds."

Actually, I'll end it with this: :moon:

Okay, I'm done doing this now::bang:
Now, onto the topic at hand...

another factor making outdoors running more difficult is the fact that you are battling wind resistance whereas with a treadmill there is really no significant wind resistance to overcome.

Great point! This has never crossed my mind. Because a treadmill is easier to run on (in my opinion) I always run on it at an incline of 1.0. It's not much, but I figure it's enough to make up for not being outside on the ground.

As for treadmill vs. elliptical, I personally like the treadmill better only because I prefer running. I do like to change it up every once in a while though and throw in the elliptical (or bike, or rarely the stairclimber).

Guava....I suppose you make a good point. If you pre-program the rig then you have to "keep up" with the belt. But my eliptical has programs on it too, in terms of intensity. Can be programmed up to 20 minutes of varying intensities. You just have to be stalwart enough to keep up the intensity through the programs.

Others....I like using my eliptical. I'd use a treadmill too if had one. I really don't care if squats,lunges and standard body-building lifts use more calories. I'm not concerned with weight loss. Nor do I feel that bodybuilding/weightlifter routines cover the entire spectrum of fitness.

Many sports,athletic endeavors, fast-twitch routines, and functional abilities will not be addressed by "doing more squats" etc.

Increasing the max bench or deadlift may work just fine for increasing the max bench or deadlift. But it is not a panacea for other modes of fitness.

Go Buffs.....You're 'people mover' belt analogy is all wrong. If the belt is moving forward and you are standing on it, additional forward propulsion will be required to move you ahead of the belt. Initial inertia has already been overcome by the fact that the person IS STANDING ON THE BELT and.....THE BELT IS NOW MOVING FORWARD. In order to get ahead, the person will apply forward propulsion IF HE WANTS TO MOVE FORWARD FASTER THAN THE BELT IS ALREADY MOVING.

On a tread mill, THE EXACT REVERSE is happening. Because the belt is moving backward, you are preventing your self from going backward with it. So you put one leg in front of the other, at a rate that matches the requirement to "stay in place". The forward propulsive force is not as evident here because you are NOT propelling yourself forward on a STATIC surface, (where the forward propulsive force must be great enough to continually move the static object (you) over the static surface (ground).

On an eliptical, there is still not the same effect as moving ahead on solid ground either because bodyweight intiates some of the force required to overcome static friction of the cycle. So your left leg moving to the rear is partially assisted by your right leg and partial bodyweight pressing down on the right.

On either machine you are using Hams and Glutes to some extent.

IMO a treadmill with a non-motorized belt would be a better option than a motorized. However, this feature seems to be found only in really cheap flimsy units.

90 % percent of the mags and sites I've visited for cardio machines end up by pegging the treadmill as the number one cardio rig. The eliptical usually gets second spot.

Is either one better? Depends what you're using it for. That's like saying "Is a mallet better than a claw-hammer?"

In the evolution of fitness equipment, no doubt somewhere down the road someone will invent a rig that takes care of the inherent shortcomings peculiar to both machines.

A treadliptical?

An eliptmill?

A treadlipticalclimber? :)

Well, I wasn't suggesting that people walk in a Frankenstein-like manner while on the treadmill ... The description was mainly aimed at illustrating how the treadmill is essentially providing the propulsive force. When you run on solid ground, you not only propel yourself forward, but you also propel yourself upward off of the ground. On a treadmill, you would still be required to propel yourself upward -- so in this respect, running on the treadmill is like running on stationary ground. However, once your lead foot hits the treadmill and moves backward, you don't have to apply the same level of backward (propulsive) force that you would on stationary ground.

Yeah, I know, I got that part of it.

I was just saying I don't think it makes that much of a difference. It doesn't feel different to me mechanically, and I just feel like if you're running with normal mechanics, your foot won't be pulled that far because it's not in contact with the belt for very long.

On second thought, maybe we should all get the Bowflex Treadclimber. Or even better, Tony Little's Gazelle. ;)

Not sure whether to add anything here. I was a physics major many
years ago, and I can confirm that aside from the air resistance, a runner
on the ground and on a treadmill are performing the exact same
exercise, as their motion is relative to the frame of the ground/belt.

However, once your lead foot hits the treadmill and moves backward, you don't have to apply the same level of backward (propulsive) force that you would on stationary ground.

Actually, it's the same. In the reference frame of the belt,the belt is
stationary and the runner is applying a propulsive force to move foward
relative to the belt. At sprinting speeds, air resistance may factor in and
make life harder for the guy running along the ground, but otherwise,the
physics are identical.

Just imagine a guy running inside a train passenger car. Assuming
the train is in uniform motion, and all the windows are covered,
he won't even know the car is moving. The train is just a
very long belt.

Thank you hankhill. I knew eventually someone would come to my defense. I was a physics major too.

I really don't care if squats,lunges and standard body-building lifts use more calories. I'm not concerned with weight loss. Nor do I feel that bodybuilding/weightlifter routines cover the entire spectrum of fitness.

If you can't think of how to cover the entire spectrum of fitness with dumbells, then you don't know dumbells.

In the evolution of fitness equipment, no doubt somewhere down the road someone will invent a rig that takes care of the inherent shortcomings peculiar to both machines.

A treadliptical?

An eliptmill?

A treadlipticalclimber? :)

A pair of dumbells and a bench?

There are certain forms of martial arts, gymnastics and functional training where dumbells and a bench isn't going to cut it.

A parallel bar rig, rings and a high/chin bar plus tumbling equipment would serve me better than a pair of dumbells and bench in that venue.

Regarding the "man on a train" scenario...

Actually I do get it.

Because he is on a train it makes no difference whether the train is moving forward or backward because the man inside is on static surface relative to himself.

Although the train is moving, the man inside and the floor of the train he is standing on are both static.

Once the train is underway it requires no force of any kind for the man inside to stand there and do nothing.

If he walks ahead it will require forward propulsive force from him.

But he will not be overcoming the forward force of the train because this has already happened and his body is moving at the same speed of the train of already.

So it would be as if he were walking on solid ground.

Now if he's on a treadmill, the "solid ground" ground underneath him is not solid or static. It is moving backward.

if he does nothing he will move backward with the belt.

To maintain his position he must put one foot in front of the other continually to allow for the distance the belt has moved under and behind him.

When his leg and foot touch the belt,and he is balancing momentarily on that leg and foot, the other leg and foot will be moving ahead.

He does not have to apply the same forward propulsive force as he would on open ground. Rather, he just has to "see the motion through" basically for each leg as the belt moves away underneath him.

This is a bit of a simplification.

But on open ground he has to overcome the fact that the ground is static and not moving. Whereas the belt is not static and is taking some of the forward propulsion required out of the equation because it is moving backward.

This is in no way the same principle as the 'man on the train" or a "people-mover belt". The physics involved there are different than the man on the treadmill.

On open ground 100 % forward propulsive force is required because the ground is static and the person is static unless he continually applies force to overcome inertia.

Where you add a factor to take part of the inertia/forward force out of the equation (in this case the moving "backward " belt of the treadmill) there has to be a thus result.)

Any physics major will tell you that you have to factor in the applied variables.

The variable here being that the man will not need to apply as much forward propulsive energy because the belt is ,in part, taking some of it out of the equation for him.

Go right ahead and run at a 5% grade on the treadmill. Then go outside and run the same distance at the same grade on open ground ( with zero wind resistance). It's not the same at all.

On open ground 100 % forward propulsive force is required because the ground is static and the person is static unless he continually applies force to overcome inertia.

Where you add a factor to take part of the inertia/forward force out of the equation (in this case the moving "backward " belt of the treadmill) there has to be a thus result.)

Any physics major will tell you that you have to factor in the applied variables.

The variable here being that the man will not need to apply as much forward propulsive energy because the belt is ,in part, taking some of it out of the equation for him.

precisely


the problem that some of these folks arent grasping is that the laws of physics do not happen in a vacuum. there are always variables to be considered. yes, on a treadmill you have to propel yourself forward but not to the degree that you do on ground. the ground under your feet outdoors isnt moving at all. rather your propulsive forces may give it that illusion. if you stand on the side of a moving treadmill, then place one foot on the treadmill, what will happen? your foot will be taken backwards with no effort of your own (yes i know you'd require energy to put one foot in front of the other so that you dont fall backwards-but its not the amount of energy required to propel a decelerating mass on the ground). the only way to make "the ground outside move backwards is to use force to propel yourself forward.

There are certain forms of martial arts, gymnastics and functional training where dumbells and a bench isn't going to cut it.

As someone who does maybe as much functional training as anyone keeping a journal here, and as someone who has coached fencing, and a billion years ago dabbled in gymnastics, I would tell you that if you know what I know about dumbells, it will cut it.

You want a guy who is as fit as a rings specialist? I'm kind of thinking that one arm bodyweight dumbell rows and straight arm pullovers is going to cover a lot of that ground.

Another way to put it is if you take an elite gymnast or martial artist, I can pretty easily come up with dumbell exercises that will challenge them. Oddly enough not necessarily requiring that much weight of dumbell.

Zen.....I congratulate you on your unwavering defense of resistance training with fixed weights.

But dumbells are no mystery. They are units of weight.

A "one arm DB bodyweight row"...in my case that would be a dumbell weighing over 190 lbs.

For straight-arm pullovers I'd need 2 dumbells weighing approx, 100 lbs each.

This might match the force I'd be hefting around while doing ring-work.

( I did lots of ring work when I was younger...also did martial arts).

If I use lighter dumbells I might get a good workout and possibly some hypertrophy but it won't be the same effect as actually doing the ring work because on the rings more muscles are involved simultaneously.

I still incorporate gymnastic training in my workouts. I have the height clearance in my facilities to do quite a few of them.

The inference I'm getting is that you could "blow the doors off anybody" with one of your dumbell workouts.

The same could be said of other venues. I'm sure a long-distance runner could shellac a bodybuilder at running. So could a rower at rowing, so could a boxer at boxing or a fencer at fencing.

I seriously doubt you could duplicate all gymnast moves with dumbells, even at lighter dumbell weights.

Dumbells are an excellent resistance training device. But to give them that "one size fits all" allocation is a bit of a stretch.

For instance, if I want to do an over-ground sled drag with a rope over my shoulder, the total mechanics of that move will not be matched by a dumbell. Unless I tie one end of the rope to a 250lb+ dumbell and drag that across the ground.

How do you duplicate a spinning back-kick with a dumbell?

Or a spinning back-fist?

Or a high axe-kick?

Or a mid-air double sommersalt off a spring board?

If you want to practise high-speed punching with a dumbell in each hand, make sure your health insurance is paid up. If the DB's weigh more than boxing gloves.

Working out on the heavy bag cannot be duplicated with a dumbell. The forces and mechanics are entirely different. e.g.:- when your fist and arm make contact with the bag.

You can't teach grappling moves with a dumbell.

Dumbells are a specific tool. For a specific job.

Sure, you can get one hell of a calorie burning workout with DB's.

But so could you by running up and down the stairs of the Empire State Building all day long.

No machine in the gym is more brutal than the rowing machine, or the ERG....when done right and keeping a quick pace. The Erg will hit those quads harder than anything and involves pretty much every other muscle as well...except chest, it seems.

Treadmill, ellipticals, running, they're all great for cardio/HIIT. Do whichever you like and therefore will be consistent with. Strive to improve your performance each week (if that's part of your goal) and vary your workouts/machines. I prefer running outdoors so that's what I do, however, i'll do the treadmill or elliptical at times to change things up. They all seem to hit different muscles since when my legs are sore from running too much, doing the treadmill seems to be ok...etc.

being a newly minted physics major myself, I can't help jumping in...


Regarding the "man on a train" scenario...

Actually I do get it.

Because he is on a train it makes no difference whether the train is moving forward or backward because the man inside is on static surface relative to himself.

one is *always* static in position regarding one's self. This is the "world revolving around me" scenario. If your frame of reference is centered around you, when you "move" you're not actually moving. The UNIVERSE is moving with respect to you.



Now if he's on a treadmill, the "solid ground" ground underneath him is not solid or static. It is moving backward.


it is "moving backward" only with respect to the room/world. In the frame of reference of the person ON the treadmill, the treadmill is static. The room/world is moving. which is exactly why....

if he does nothing he will move backward with the belt.



this may be hard to understand at first glance, but try to wrap your mind around it. There is no hierarchy of frames-of-reference (FOR). The FOR of planet earth is not superior to or more valid than the FOR of the sun or the moon or your big toe. The frame of reference of one speck on the surface of the treadmill is equally valid.

I know this feels kind of like a pot-head "whoa, totally mind-blowing, dude..." statement. Think of it this way: you're floating in an unlimited white expanse with no visual identifiers (kind of like Matrix I, where Morpheus is describing the current state of the world). You see two balls, one green and one red, that are continually growing further apart. How can you tell which one is moving? How can you tell if *both* of them are moving? You can't. That's because it depends on your frame of reference.


Go right ahead and run at a 5% grade on the treadmill. Then go outside and run the same distance at the same grade on open ground ( with zero wind resistance). It's not the same at all.

I think that if one were to take a mile of the plastic that the treadmill's walking surface is made of and suspend it outside (exactly as it is suspended in a treadmill) on a 5% grade with zero wind resistance, anyone running a mile outside on a "stationary" treadmill would have exactly the same experience as when they are running the same mile on a "moving" treadmill indoors.

Anyone who has gotten this far -- you're a physics enthusiast, arentcha? :D

From a practical point of view, I think almost everyone agrees that running outdoors is more difficult than running on a treadmill. Same speed, same incline.

Then why do the physicists ;) all say that there should be no difference in work running on a stationary surface vs a moving surface?

Primarily because they qualify their arguments with absolutes. A runner running EXACTLY 5 mph on the the treadmill expends the same amount of energy as another running EXACTLY 5 mph outdoors. No change in speeds allowed, no hills, no sprints, no rest stops and go's.

In the real world, we are slowing and speeding up all the time. We are encountering hills. We are stopping at intersections and stopping for water. Then we are restarting. THAT'S where the difference is. It takes more physical effort to increase speed outdoors than on the treadmill.

That's my two cents.

I understand whats going on here... The energy expended on a treadmill is exactly the same as you would use outside on a "speculative stationary ground".

The Ground only appears stationairy becuase, you ourself are stationary. Place a Kilometre of rubber down moving at 5kmph and a runner alongside the treadmill doing the same speed. Sure the outdoor runner will move away, and the treadmill runner will stay still. But they have still covered the same distance under the same or near enough conditions.

What throws me off. Is the ground appears stationary but isn't in respect to the Earths Spin. Is the actuall energy exerted amplified by the speed reduction or increase in the relative speed of the "universe".

What throws me off. Is the ground appears stationary but isn't in respect to the Earths Spin. Is the actuall energy exerted amplified by the speed reduction or increase in the relative speed of the "universe".

The earth is not spinning; it is still. And the universe revolves around it.

The earth is not spinning; it is still. And the universe revolves around it.

LMAO!