sophiecentaur said:
Yes, you are being perfectly polite, which is why we continue to converse with you. However, your initial question was not complete and was not asked in Scientific terms. That was the "behaviour" I was referring to.
Ok see your point. Sorry I asked it in layman’s terms, but people have got to start somewhere.
sophiecentaur said:
From your first post:
"But what would be the impulse/force on/from the components/parts if the weight was lowered at the above vilocity, and for how long in 10ths or whatever in time would that higher force have to be until the normal acceleration forces of the lift at rest."
Yes, that was quite a bad post.
sophiecentaur said:
Impulse and force are two different things. That's why two different words are used in Physics.
Yes I see that, here is my interpretation, hope you comment. I would say Impulse is a force acting on an object over a short period of time; like in the peak forces in my repetitions, as when I am lowering on the eccentric the weight, at say 2m/s for 20 inch, I then have to use my highest force I can in Milly seconds to slow, stop and restart the weight force the concentric. If I was using ? 80 pounds, I “think” the impulse force ON my muscles for say a tenth of a second could be from 120 to 160 pounds ?
Then to me the rest of the concentric lift is the force used by the muscles to lift. Both are forces but one is the fast impact force, then there is the lower force to carry on the lift ?
This “very” high impact/impulse force, puts huge tensions on the muscles, and is a BIG part of this debate, as I say that the very high impulse with the high forces from the accelerations cannot be made up or balanced out by the lower forces of the slow repetitions. As not only do the muscles doing the fast have higher forces on the accelerations, they have the “EXTRA” forces from the say tenth of a second huge impact/impulse forces. I am sure D. has not added these in, actually I know he has not added these in, if you have time could you comment on that as well please, the huge impact/impulse force on the muscles from the fast that the slow does not have, as 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.
sophiecentaur said:
Likewise, for Force and Strength. So you ask about the relationship between one, non specific quantity and another, non-specific quantity. Is that scientific?
Ok sorry, see your point again.
But is not a force a push or pull, and that’s what the muscles strength does.
sophiecentaur said:
You claim that your machine tells you the force involved (in N) but then say that it reads electrical activity in μV. When you 'tense up' your arm, there is no net force at all (it stays still, in its original position) but there is loads of muscle activity,
Not fully with you on that one sorry, or maybe reading you wrong. As when I tense up my arm with the pads on the moving muscles, let's say the biceps and foararm in the curl or arm flextion, if I just tence those muscles the reading on the machine tells me, if I just hold the weight half way up the machine tells me, and when I miove the weight up and down the machine tells me, and tells me the high signals, with my muscles are producing high force, and the lower end of the signals where my muscles are producing the lower force. So this is a net force, when you tense and when you lift.
sophiecentaur said:
as your machine would show, but the antagonistic muscles are producing equal and opposite force.
No, only the antagonistic do “not” produce equal and opposite force in any barbell exercises, they produce very little force, maybe as little as 5 or 10% the agonist muscles do all the lifting and all the lowering. {actually the lowering or eccentric portion of the lift which the biceps and forearm does, {as well as the concentric} able a person to lower 40% more under control, say lower in 6 second, than the person can lift for their 1RM.
So no the antagonistic muscles are not producing equal and opposite force. As the biceps are the curling or flexing muscles, and the triceps are the extending muscles.
sophiecentaur said:
So there's no direct connection between muscle activity and force produced.
Yes there is, it’s a direct comparison. As if I lift 30% then 80% the readings like the peak force and average force will be far higher.
sophiecentaur said:
That is unless you have electrodes on every muscle group and the machine can do some complicated 'addition' of the effects of all the muscles.
You only need the pads on the lifting muscles, as these are the ones producing the force for both up and down.
Yes the machine does do very complicated equations instantly all the time.
sophiecentaur said:
You are still after some relationship between that muscle activity and the measurable work done on a weight when lifting it. But if it's possible to have loads of muscle activity and Zero work done, then there clearly is not one. Can you not accept that?
Yes I understand the concept of work, if I do not move the weight no work has been done, but there is still muscle activity, energy and force being used.
sophiecentaur said:
There is really no more to be said on the topic (except for another acre of figures about rep rates and pounds lifted).
I find it odd you say that, but after reading the about you might differ.
What about this question then ? I am sure you can talk or understand scenarios outside of physics ? Like other branches of physics, kinology, biomechanics.
Or, just thought of this, let’s say your back at university, and you have to do a practical test and scenario for your PhD, and the Lecturer asks you the below, and you have to answer. Or could you just have a go for me, or suggest another way I can ask it, but as a physics adviser, I thought you would like to try and work out how the equations do not add up in the real World tests/experiments as in below ? Please ? As I don’t see how you can step outside the box, as I thought all physics should be tested in the real World after they have been calculated on paper.
The Question.
You always fail faster about 50% faster in the faster repetitions, so if you fail faster, you “HAVE” used up your temporary force/strength, as you hit muscular failure faster thus you cannot lift the weight anymore. To me, if both Clones started the fast and slow lifting at the same time, as the slow Clone are still lifting the weights when the fast Clone has hit muscular failure and unable to lift the weight anymore, this “is/seems irrefutable, or categorically right to me, and I am not trying to sound smug or anything here, but if the slow Clone is still moving the weight, then the fast Clone “has” used up more overall or the total force/strength they had faster, if you see my point, please do you see what I am saying here ?
sophiecentaur said:
I can only suggest that you approach the manufacturers of your machine and ask them for their opinion.
These machines are/have been used in Hospitals and sports facilities for years, they are as efficient as your calculator, actually they are calculator/computers in another form. The machines are used as much as the everyday car; they are very well known and used.
http://medical-dictionary.thefreedictionary.com/electromyography
sophiecentaur said:
They may well be more prepared to speak you language as it is in their interest to sell as many of those machines as they can. I think they will tell you that the machine gives a good indication of how much energy the muscles are transferring and / or the forces. I have no problem with that (the neurological application of the machine seem very worth while). They may even launch into some link between that and the mechanical work done. That will make you happy. Great, but it won't make the Science any more valid.
IF, you want to prove your physics equations right, you would need to “try” and answer the question above, and say why the below happens in the real World, as I am in contact; New Scientist Magazine, Physicstoday Magazine and Physics World Magazine. If you could be the first to solve the puzzle of how and why the equations and real World tests on this Phenomena is, maybe you could be in these Mags.
Thank you for your time and help.
Wayne