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Impulse/force in pounds for the time frame

by waynexk8
Tags: frame, impulse or force, pounds, time
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douglis
#145
Feb20-12, 02:03 PM
P: 148
Quote Quote by waynexk8 View Post
I move 80 pounds up and down 20 times in 10 seconds, you lift 80 pounds up and down 1 time in 10 seconds, I use more energy.
More energy yes...more peak force yes....but the average force is 80 pounds in both cases hence the forces "make up".

Greater energy expenditure does equate greater force, if you move the same weight faster in the same time frame.

Wayne
Well...since you discovered a new law...all you have to do is to prove it somehow or else it will remain a figment of your imagination.
sophiecentaur
#146
Feb20-12, 04:45 PM
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Wayne
You still seem to be insisting that your muscles and the way your body controls them are much simpler than they are. No one has argued that doing things faster can knacker you more and can damage muscles. It's just that you seem to insist on having a simple Physics formula - but not real Physics - your brand of Physics, in which all the names are jumbled up and re defined. No wonder we can't help you.
waynexk8
#147
Feb20-12, 06:11 PM
P: 399
Quote Quote by douglis View Post
1)The average force is the weight.
What your trying to say, or think, is that if you hold 80 pounds half way up for 10 seconds, and I move the weight up and down 20 times in 10 seconds, that we have both put out the exact same total/overall force thus tension on the muscles, right ???

ďIfĒ that were so, then why does anyone that uses 80% of their 1RM {repetition maximum} fail in lifting the weight, or/and hit momentary muscular failure say 50% faster ??? I will tell you why. Its because the higher force needed for the accelerations, and for the decelerations, as on the decelerations you are still pressing with as much force as you can, its only on the very last portion of the lift that you immediately lower force very fast for the transition from positive to negative, then immediately on the negative there is force from the muscles thus tension on the muscles.

So there we have it, you fail faster, and this is basically because the faster reps ďareĒ putting more tension on the muscles, so they fatigue/tire 50% faster. But your saying they donít they fatigue/tire faster or put more tension on the muscles, your saying that they fatigue/tire 50% faster, because they use up more energy, and they use up more energy not because they are moving with greater acceleration = more force, or travelling with more velocity = more force, your saying they just they fatigue/tire faster because of no reason than they use more energy for some unknown reason, is that right ???

You also think that your medium forces can make up or balance out my higher forces, but you cannot say why ??? However I can say why I say itís not, as I move the weight 6 times more distance, use more power, thatís more energy and more work done.

Question to all please
If I was to lift and try to throw the same weight with open hands, are you saying then I would use more force ???

Quote Quote by douglis View Post
2)The peak force requires more data.If you use an accelerometer you can find the peak acceleration and then the peak force.
Yes.

Quote Quote by douglis View Post
3)Total or overall force doesn't exist in physics.What you're looking for is the integrated EMG or maybe you can describe it with gravity's impulse which is the same in both cases of your example(weight X 6 seconds).
So what about tension, can physics find out how much tension was put on so and so ???

No, thatís where the EMG and force plate come into action, these work out the total or overall force, or and average force.

If you think total or overall force does not exist in physics, why are you saying both lifts have the same total or overall force ???

We could call this total of overall force, total force with respect to time, so if I put 100 force on 80 pounds for 4 seconds, and you put 80 force on 100 pounds for 4 seconds, who put out the total or overall force ??? As I would have moved the weight further, that would categorically say I did, right ??? If not why ??? If I put 100 force on 80 pounds for 4 seconds, and you put 80 force on 100 pounds for 6 seconds, who put out the total or overall force ??? As I would have moved the weight further, that would categorically say I did, right ??? if not why ??? If I put 100 force on 80 pounds for 4 seconds, 79 pounds of force for 2 seconds, and you put 80 force on 100 pounds for 6 seconds, who put out the total or overall force ??? As I would have moved the weight further, that would categorically say I did, right ??? If not why ??? And ??? Means I am please asking you a question.

You seem to think, that as I move the weight further, I donít use more total or overall force to do this ???

Wayne
sophiecentaur
#148
Feb20-12, 06:16 PM
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I do not subscribe to the term "total force". There is no such quantity in Physics. So the rest of your post means nothing, I'm afraid.
waynexk8
#149
Feb20-12, 06:25 PM
P: 399
Quote Quote by sophiecentaur View Post
Wayne
You still seem to be insisting that your muscles and the way your body controls them are much simpler than they are.
That are far more complicated, and am trying to simplify things, as instead of muscles, we can just say this is a machine pushing the muscles with force, [b]and if you put too much strain on that machine, it will fail faster than the machine you donít put as much strain, and strain in this case is higher force output, and thus more tension on the machines moving parts. Put to more strain on the machine, as in making it move as fast as it can with very high accelerations, and there will be too much tension on the machine, and it will fail. Same are the car that have been driven further, its parts fail faster, and thatís because more acceleration force thus tensions on the moving parts.

Quote Quote by sophiecentaur View Post
No one has argued that doing things faster can knacker you more and can damage muscles.
Ok thx for that.

But I see it as the higher acceleration forces, anytime you move faster, it could be 3/3 against 10/10 in the same time frame, but every time you try and move faster, there has to be more acceleration, thus higher forces on the muscles.

Quote Quote by sophiecentaur View Post
It's just that you seem to insist on having a simple Physics formula - but not real Physics - your brand of Physics, in which all the names are jumbled up and re defined. No wonder we can't help you.
Sorry I am trying, but if D. is right, then physics does not have an equation for total or overall force, in the same time frame ďcould not we be the first to try and find one ???Ē As physics is physics, we should be able to work this out somehow, or is it the power equation, power = force acceleration ??? Thus we all know there is more power in the faster, if more power and more power = more force acceleration, then am I not right ???

Will read the other posts later and get back to them, thank you for your time and help again.

What if a bought a force plate ???

Wayne
douglis
#150
Feb21-12, 03:14 AM
P: 148
Quote Quote by waynexk8 View Post
your saying they just they fatigue/tire faster because of no reason than they use more energy for some unknown reason, is that right ???
No...the reason is very well known.Biology studies tell us that the fluctuations of force are more energy demanding.

You also think that your medium forces can make up or balance out my higher forces, but you cannot say why ???
Everyone has told you why.Because the average force is the weight in any case.This by definition means that "your" higher peaks are exactly balanced by "your" lower peaks and the result is "my" medium force(the weight).

ďcould not we be the first to try and find one ???Ē
Wayne
First learn to use the basic physics terms and leave your big plans for the much later future.
waynexk8
#151
Feb22-12, 11:51 AM
P: 399
But in full tomorrow night and I must apologise for not answering some posts yet, I will get back to them, and thank you all again.

The below is again for D. it’s from “another” EMG expert. And would be interested to see how/or why he was wrong, and thought my EMG was wrong, mind you it’s not the first time you have been wrong, you had metabolism wrong, energy wrong, your rocket theory, now EMG, however we all get things wrong and you’re a very clever person. I got my training wrong for 15 years, doing the slow, so I cannot pass judgment.

Hi Wayne,

I got the email you sent to Motion Labs - we have a cooperation with them. The company I work for - prophysics AG in Zurich, Switzerland - market and sell the myon EMG system as well as the proEMG data capture and analysis software.

You can check out details of our prophysics on www.myon-prophysics.ch

I read through your email. EMG measures the electrical activity of muscles using electrodes attached to the skin surface above the muscle's belly. To answer your direct question, whether to use Integrated or RMS calculation, the answer is probably RMS. The reason for this is that the RMS calculation is the "standard" way of representing the average voltage amplitude of the signal, and this is correlated with the muscle power.

Wayne
sophiecentaur
#152
Feb22-12, 12:20 PM
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Wayne
For someone who claims to know nothing of Physics, you have become very assertive and a bit too stroppy for my liking.
Nothing I have ever written about the Physics of this topic is wrong. It's just too basic and glaringly obvious. The same goes for Douglis's statements about Physics.

The stuff about EMG results is not the Physics of moving masses up and down. I's about what your Muscles are doing. The fact is that, even when lowering something, your muscles are using energy (unless you just drop it on the floor). Hence, there is no direct relationship between Energy Expended in your muscles and Work Done on the Weights you lift. That is the beginning and end of the whole topic and neither you nor your fellow EMG users can change it.

The readings on your EMG machine can give you a lot of useful information about your Body and that's all.

I can't actually understand what you are trying to achieve here and slagging people off for making statements that you clearly don't actually understand is not getting us anywhere.
douglis
#153
Feb22-12, 02:08 PM
P: 148
Quote Quote by waynexk8 View Post
it’s not the first time you have been wrong, you had metabolism wrong, energy wrong, your rocket theory, now EMG, however we all get things wrong and you’re a very clever person.
Show me where I was wrong.
From physics point of view...you can not possibly know if you spend more energy by lifting and lowering a weight than just holding it for the same duration.Only biology has the answer...so I was never wrong.It was supposed to be a physics discussion.
Hi Wayne,

I got the email you sent to Motion Labs - we have a cooperation with them. The company I work for - prophysics AG in Zurich, Switzerland - market and sell the myon EMG system as well as the proEMG data capture and analysis software.

You can check out details of our prophysics on www.myon-prophysics.ch

I read through your email. EMG measures the electrical activity of muscles using electrodes attached to the skin surface above the muscle's belly. To answer your direct question, whether to use Integrated or RMS calculation, the answer is probably RMS. The reason for this is that the RMS calculation is the "standard" way of representing the average voltage amplitude of the signal, and this is correlated with the muscle power.

Wayne


Check the graph.Anyone who has the intelligence to breathe can understand that the RMS amplitude is NOT the average.
waynexk8
#154
Feb23-12, 07:42 PM
P: 399
Quote Quote by sophiecentaur View Post
Wayne
For someone who claims to know nothing of Physics, you have become very assertive and a bit too stroppy for my liking.
Sorry about that, what part did you mean please ??? I am not that type honest, it’s just me a D. have been debating so long, we have often said the odd thing to each other, nothings meant by it honest.

I did not say I knew nothing of physics, it’s more the physics theory I do not know.

Ok, “please” sophiecentaur, one of the things that could have made me stroppy, is that I do not get why you or D. cannot answer this one, please “could” you ???

1,
I lift a weight up from a motionless start, up 500mm in .5 of a second.

2,
A weight is being lowered under control, moving 500mm in .5 of a second, the mm before it hits the ground, I then have to try and lift it up 500mm in .5 of a second.

3,
As of the acceleration components, when moving down with that acceleration, the weight will appear {not sure of the right physics saying for this sorry ???} to be heaver, or have more force than if it was motionless. So it is going to be heaver/harder to lift, thus I “will” need more force than the first lift, think we all agree there ???

4,
How much more force please.

5,
If you can’t work out how much more force, and please you can add in your own accelerations for this if you need to. But if you can’t work it out, do you agree that the force needed would be about, and this is a very rough guess ??? 50% more force for .2 of a second, then the same force as the first lift ???

6,
When you two, or anyone else are compeering my fast lifts force, and your slow lifts force, which modal are you compeering your lift two, the lift started from a motionless start, or the lift that is being lowered first then lifted ??? I would say it’s the motionless lift, am I right or wrong please ???

Quote Quote by sophiecentaur View Post
Nothing I have ever written about the Physics of this topic is wrong. It's just too basic and glaringly obvious. The same goes for Douglis's statements about Physics.
How is it obvious ??? As when using 80% of your 1RM {Repetition Maximum} you fail to lift the weight again, or you hit momentary muscular failure 50% faster on the faster reps, this must surely mean you have used up your temporary force faster, it can’t mean you have used up your temporary force slower, or you would still have force left, but you don’t, you don’t have any force left, so that can mean one think only, that on the fast you are using more force per unit of time, if not please explain your way of thinking. I use more energy in the same time frame; I move the weight far far far further in the same time frame.

I never said you did wrote anything wrong, I might have said I think you could have left something out, like not adding in all the variables, or kinology, or like in my 1 to 6 above. But what I don’t understand, and no one have tried to explain, is that when my peak acceleration forces are say a 100% or 100 pounds of force, how do you think that your 80% or 80 pounds of force can make up the 100 pounds of force, when its only 80 pounds, how can 80 ever be as high as a 100 ??? The only way the 80 pounds of force could make this extra force up, or the shall we say the 100 pounds of tension on the muscles to the 80 pounds of tension on the muscles, is if the 80 pounds of tension was on the muscle far far far longer, please do you agree there, if not, how does the 80 pounds of tension make up the higher 100 pounds of tension on the muscles, as a 80 pounds tension, can never be as high as the 100 tension, as how could 80 pounds feel like 80 pounds on the muscles ??? Its impulse, force with respect to time. A small force applied for a long time can produce the same momentum change as a large force applied briefly, because it is the product of the force and the time for which it is applied that is important. But in our case the reps, lifts are done for the same time frame.

Quote Quote by sophiecentaur View Post
The stuff about EMG results is not the Physics of moving masses up and down. I's about what your Muscles are doing. The fact is that, even when lowering something, your muscles are using energy (unless you just drop it on the floor). Hence, there is no direct relationship between Energy Expended in your muscles and Work Done on the Weights you lift. That is the beginning and end of the whole topic and neither you nor your fellow EMG users can change it.
The EMG does not compute energy ??? The EMG computes the electrical signals the muscles give out, the more electrical signal = more muscle activity = more muscle force, of can we say muscle strength used. So I think it is the physics of the forces, and its adding in, or saying that the faster you move, the more force is used, its adding in the peak forces of the faster accelerations of the faster reps, and in my opinion it shows that the slow forces cannot make up or balance out the higher force or tensions that the faster has put on the muscles, thus it reads out higher for the fast. That is why more energy is used; it has to use more energy as of the higher forces from the higher velocities and accelerations. Also that’s why the fast mores the weight 6 times further, as it takes more force to move a weight further in the same time frame, yes ???

Quote Quote by sophiecentaur View Post
The readings on your EMG machine can give you a lot of useful information about your Body and that's all.

I can't actually understand what you are trying to achieve here and slagging people off for making statements that you clearly don't actually understand is not getting us anywhere.
Sorry honestly did not try to slag you off, not sure where you think I did that, but if you think that, I will, and will do it now, I apologise for anything I have said, and it was not meant at all.

Ok, I imagine you know or have heard what a force plate/platform is ??? If I buy or have tests done, and that state the average and total or overall forces are higher in the fast, like the EMG states, what would you say then ???

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

Will get back to the others tomorrow. Again, thank you for your time and help; I only want a friendly debate.

Wayne
sophiecentaur
#155
Feb24-12, 06:30 AM
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Quote Quote by waynexk8 View Post

I did not say I knew nothing of physics, itís more the physics theory I do not know.


Wayne
This absolutely sums up what's wrong with your approach. Physics IS THEORY. If you don't use the theory then anything you have to say is just idle chit chat.

It explains why you seem incapable of stating a question in less than ten paragraphs and incapable of understanding an answer that takes up a single line.
Would you ever ever ever challenge a mathematician about something on the grounds that you know Maths but not the 'theory'?
You do not believe that Physics cannot answer your question because you just don't know the Physics. Until you are prepared to learn some of the 'theory' you will never get this. Stick to arm waving.
waynexk8
#156
Feb24-12, 06:26 PM
P: 399
Quote Quote by sophiecentaur View Post
This absolutely sums up what's wrong with your approach. Physics IS THEORY. If you don't use the theory then anything you have to say is just idle chit chat.

It explains why you seem incapable of stating a question in less than ten paragraphs and incapable of understanding an answer that takes up a single line.
Would you ever ever ever challenge a mathematician about something on the grounds that you know Maths but not the 'theory'?
Sorry, yes my writings are long.

If I had four marbles on the table, and the mathematician took 2 away, and said I still have 4 there, then yes I would challenge his theory with my practical World experiments.

Quote Quote by sophiecentaur View Post
You do not believe that Physics cannot answer your question because you just don't know the Physics. Until you are prepared to learn some of the 'theory' you will never get this. Stick to arm waving.
I am trying to learn, however I think you could also try to see how theory does not always provide the truth, as in the fast rep fails at lifting first, that ďmustĒ mean, that the person doing the fast, used more muscle force per unit on time, if not why does the fast have no force to pick up the 80 pounds, but the slow does ??? Also, how does the fast move the weight 6 times futher in the same time span, how does the fast use more energy in the same time span, if its not as you two say using more force up per unit of time.

Physics, or right/correct physics, is only right/correct physics, when the theory is proven with practical experiments, unless that, it stays an unproved theory.

I am not arm waving, I have come here asking and hoping for answer to questions, so I ask quite simple questions like the below, but I get no answer, please I do not understand why you canít answer the below. Not being sarcastic here, but itís the only thing I can think of, you do understand what I am saying/asking below ??? If not please say, as its looks very straight forward to me, please tell me if the below is the wrong way to ask, or just say why you will not answer, as I do not get it. I can here to ask some friendly polite questions, and it seems more of a match to put me down, I just donít understand this.

1,
I lift a weight up from a motionless start, up 500mm in .5 of a second.

2,
A weight is being lowered under control, moving 500mm in .5 of a second, the mm before it hits the ground, I then have to try and lift it up 500mm in .5 of a second.

3,
As of the acceleration components, when moving down with that acceleration, the weight will appear {not sure of the right physics saying for this sorry ???} to be heaver, or have more force than if it was motionless. So it is going to be heaver/harder to lift, thus I ďwillĒ need more force than the first lift, think we all agree there ???

4,
How much more force please.

5,
If you canít work out how much more force, and please you can add in your own accelerations for this if you need to. But if you canít work it out, do you agree that the force needed would be about, and this is a very rough guess ??? 50% more force for .2 of a second, then the same force as the first lift ???

6,
When you two, or anyone else are compeering my fast lifts force, and your slow lifts force, which modal are you compeering your lift two, the lift started from a motionless start, or the lift that is being lowered first then lifted ??? I would say itís the motionless lift, am I right or wrong please ???

Quote Quote by sophiecentaur View Post
Nothing I have ever written about the Physics of this topic is wrong. It's just too basic and glaringly obvious. The same goes for Douglis's statements about Physics.
How is it obvious ??? As when using 80% of your 1RM {Repetition Maximum} you fail to lift the weight again, or you hit momentary muscular failure 50% faster on the faster reps, this must surely mean you have used up your temporary force faster, it canít mean you have used up your temporary force slower, or you would still have force left, but you donít, you donít have any force left, so that can mean one think only, that on the fast you are using more force per unit of time, if not please explain your way of thinking. I use more energy in the same time frame; I move the weight far far far further in the same time frame.

I donít understand, and no one have tried to explain, is that when my peak acceleration forces are say a 100% or 100 pounds of force, how do you think that your 80% or 80 pounds of force can make up the 100 pounds of force, when its only 80 pounds, how can 80 ever be as high as a 100 ??? The only way the 80 pounds of force could make this extra force up, or the shall we say the 100 pounds of tension on the muscles to the 80 pounds of tension on the muscles, is if the 80 pounds of tension was on the muscle far far far longer, please do you agree there, if not, how does the 80 pounds of tension make up the higher 100 pounds of tension on the muscles, as a 80 pounds tension, can never be as high as the 100 tension, as how could 80 pounds feel like 80 pounds on the muscles ??? Its impulse, force with respect to time. A small force applied for a long time can produce the same momentum change as a large force applied briefly, because it is the product of the force and the time for which it is applied that is important. But in our case the reps, lifts are done for the same time frame.
Quote Quote by sophiecentaur View Post
Originally Posted by sophiecentaur
The stuff about EMG results is not the Physics of moving masses up and down. I's about what your Muscles are doing. The fact is that, even when lowering something, your muscles are using energy (unless you just drop it on the floor). Hence, there is no direct relationship between Energy Expended in your muscles and Work Done on the Weights you lift. That is the beginning and end of the whole topic and neither you nor your fellow EMG users can change it.
The EMG does not compute energy ??? The EMG computes the electrical signals the muscles give out, the more electrical signal = more muscle activity = more muscle force, of can we say muscle strength used. So I think it is the physics of the forces, and its adding in, or saying that the faster you move, the more force is used, its adding in the peak forces of the faster accelerations of the faster reps, and in my opinion it shows that the slow forces cannot make up or balance out the higher force or tensions that the faster has put on the muscles, thus it reads out higher for the fast. That is why more energy is used; it has to use more energy as of the higher forces from the higher velocities and accelerations. Also thatís why the fast mores the weight 6 times further, as it takes more force to move a weight further in the same time frame, yes ???

Wayne
waynexk8
#157
Feb24-12, 06:51 PM
P: 399
Quote Quote by douglis View Post
Show me where I was wrong.
From physics point of view...you can not possibly know if you spend more energy by lifting and lowering a weight than just holding it for the same duration.Only biology has the answer...so I was never wrong.It was supposed to be a physics discussion.
D. you can surely work out the power used in both ??? Surely you must know that if you move something further in the same time frame you need more energy, thatís goes for everything, then itís in every calorie counting book and site and nutritionist have know this for 100s of years, I also showed you how they work it out in a sealed room. Then after years it was a physicist who worked it out for you with physics and told you.

LOOK, please letís forget about that, as you did immediately say you was wrong when you was, I salute you for that, I will and do not want to rub it in every again, so sorry.

No its not just a physics debate, itís a World wide debate, and whatever needs to be added in, to answer the question, will be.

Problem is, you do not answer questions.


Quote Quote by douglis View Post


Check the graph.Anyone who has the intelligence to breathe can understand that the RMS amplitude is NOT the average.
So now you are saying that two people that make work with and use EMG machines are wrong ??? Please tell me what your graph is supposed to mean and why you made it that way, in other words please explain it in full, you never explain anything, then please send an E-mail to these people with my return headings, and tell them how/why you think they are wrong.

E-mail, sales.i@motion-labs.com

Subject, Re: [From Website] to Edmund Cramp.

E-mail, roren@prophysics.ch

Subject, Re: Your email regarding EMG systems

Then please try to answer the below, and if you say I run out of force because of I used up the energy fast, I know that, the question is sort of why did I use up more energy doing something faster ??? Did I use up more because I was using more force per unit of time, the same, or less. But the main issue is the force, the energy is ďonlyĒ the supply, and we are on about the force, the energy supply. as in the fast rep fails at lifting first, that ďmustĒ mean, that the person doing the fast, used more muscle force per unit on time, if not why does the fast have no force to pick up the 80 pounds, but the slow does ??? Also, how does the fast move the weight 6 times further in the same time span, how does the fast use more energy in the same time span, if itís not as you two say using more force up per unit of time.

Wayne
sophiecentaur
#158
Feb25-12, 01:02 AM
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Only an instrument that measures what is happening to the weights themselves can measure the work involved and the forces involved. The EMG doesn't do this so it is not contradicting the Physics.
You are clearly not "trying to learn". Not even one small step at a time. Because you disregard every basic part of theory, preferring the 'but surely' argument and 'it stands to reason'.
You dismissed my analogy concerning a mathematician by quoting an example where the Mathematician was not right and had no proper reasoning behind his result. But you argue against the RMS thing and that is totally Maths.
douglis
#159
Feb25-12, 03:45 AM
P: 148
Quote Quote by waynexk8 View Post
LOOK, please letís forget about that, as you did immediately say you was wrong when you was, I salute you for that, I will and do not want to rub it in every again, so sorry.
As always you misunderstood what I admited I was wrong.
I was wrong from biology point of view.From physics point of view I was perfectly right and you're saying nonsense.You can't possibly know if you spend more energy if you lift a weight 10 times up and down or you just hold it for 10 seconds.

No its not just a physics debate, itís a World wide debate, and whatever needs to be added in, to answer the question, will be.
OMG...you're totally delusional!What world wide debate you idiot?
It's just a couple of us with superhuman patience trying to explain basic physics to you.

So now you are saying that two people that make work with and use EMG machines are wrong ??? Please tell me what your graph is supposed to mean and why you made it that way,
The graph is not mine it's from the first site I found when I googled "rms amplitude".

The RMS is not the average.This is not offered for discussion....it's basic maths.You don't have to mail professors!

Check the below numbers:
-2, 5, -8, 9, -4

Their average is 0 but their RMS is 6.16.
The RMS is NOT the average.It's the quadratic mean.You probably don't have a clue what that means so you have to trust the link and me.
http://www.analytictech.com/mb313/rootmean.htm
Then please try to answer the below, and if you say I run out of force because of I used up the energy fast, I know that, the question is sort of why did I use up more energy doing something faster ???
I've tried so many times to explain that the force-energy relation is not linear and greater energy expenditure doesn't equate greater force.
I'm sure by now that that's way beyond your intelligence.
douglis
#160
Feb25-12, 06:23 AM
P: 148
I stop here any physics related discussion with Wayne because obviously is a waste of time.
What's the point anyway?The below study is exactly what he's looking for.

Quote Quote by waynexk8 View Post
as in the fast rep fails at lifting first, that ďmustĒ mean, that the person doing the fast, used more muscle force per unit on time

Wayne
I have shown you the absolute proof that this is nonsense with a real study but you choose to ignore it.

Take a look again:

The fast push ups failed at 81.2 sec while the slow push ups failed at 101.2 sec.It's obvious that the fast push ups had greater rate of energy expenditure(see table 1).

BUT the Total Muscle Activation(for the pectoralis major for example) for the fast push ups is 2114.23 while for the slow push ups is 3121.81(see table 3).

So the muscle activation per second for the fast push ups is 2114.23/81.2=26.04
and the muscle activation per second for the slow push ups is 3121.81/101.2=30.85

http://jmbe.bme.ncku.edu.tw/index.ph...ewFile/635/839
Conclusion:
greater rate of energy expenditure does NOT equate greater muscle tension per unit of time.In fact,in the case of push ups,the exact opposite is true.

End of discussion.
waynexk8
#161
Feb25-12, 10:58 AM
P: 399
Quote Quote by sophiecentaur View Post
Only an instrument that measures what is happening to the weights themselves can measure the work involved and the forces involved. The EMG doesn't do this so it is not contradicting the Physics.
Itís the muscles themselves that are exerting the force. For every reaction, there is an opposite reaction, so if you measure the work or the force from the muscles or the force moving/on the weight, you will find the reading.

But itís the muscles forces we are after, or the tensions on the muscles, thatís the forces from the muscles forces onto the weights, with the opposite reaction forces creating tensions on the muscles, and as the EMG takes the muscle activity = muscle force, more muscle activity = more muscle force, yes ???

When you say work, do you mean the mechanical work, the product of a force times the distance through which it acts, work of the force, we know the fast does more work, or more work of the force, so is not that more force if itís done more work, work of the force ???

Quote Quote by sophiecentaur View Post
You are clearly not "trying to learn". Not even one small step at a time. Because you disregard every basic part of theory, preferring the 'but surely' argument and 'it stands to reason'.
Sorry, when I say surely, I am more thinking out loud; please donít think anything of it.

Quote Quote by sophiecentaur View Post
You dismissed my analogy concerning a mathematician by quoting an example where the Mathematician was not right and had no proper reasoning behind his result. But you argue against the RMS thing and that is totally Maths.
See your point on the analogy concerning a mathematician; yes suppose I was wrong there, but just making a point.

Another thing, I have not been explained what RMS is ??? But then again, I could say that you are now disagreeing with people who make and work with EMG machines, and two of these stated to measure the total or overall force output of the muscles, RMS is about the best.

"Please" could you ansner this ??? If not please state why.

1,
I lift a weight up from a motionless start, up 500mm in .5 of a second.

2,
A weight is being lowered under control, moving 500mm in .5 of a second, the mm before it hits the ground, I then have to try and lift it up 500mm in .5 of a second.

3,
As of the acceleration components, when moving down with that acceleration, the weight will appear {not sure of the right physics saying for this sorry ???} to be heaver, or have more force than if it was motionless. So it is going to be heaver/harder to lift, thus I ďwillĒ need more force than the first lift, think we all agree there ???

4,
How much more force please.

5,
If you canít work out how much more force, and please you can add in your own accelerations for this if you need to. But if you canít work it out, do you agree that the force needed would be about, and this is a very rough guess ??? 50% more force for .2 of a second, then the same force as the first lift ???

6,
When you two, or anyone else are compeering my fast lifts force, and your slow lifts force, which modal are you compeering your lift two, the lift started from a motionless start, or the lift that is being lowered first then lifted ??? I would say itís the motionless lift, am I right or wrong please ???


Wayne
sophiecentaur
#162
Feb25-12, 11:57 AM
Sci Advisor
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P: 11,947
I am not disagreeing with what the EMG people are saying. The problem is that you do not seem to understand what they are saying and how it applies to your question.
Why should you need to have RMS explained any more. It isn't an explanation that you need. What you need to do is to use the definition to work out some numbers yourself. Douglis has given you a perfect worked example.

I cannot be bothered to answer that question because it is just a smoke screen to protect you from going to the trouble of working stuff out for yourself.


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