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Most force/strength used in the same time frame

by waynexk8
Tags: force or strength, frame, time
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Zula110100100
#37
Nov26-11, 12:53 PM
P: 253
Yeah...I would say 41..and read it 40+(40*0)+1 = 40+0+1 = 41

I want you to do that expiriment because I think it will show that activity does not equal force, I think if you hold 20lbs for 1 second, it will be some amount that is less than double activity to hold 40lbs for 1 seconds.

In my opinion you need to change your angle of attack, the answer given for applied force obviously doesn't give you what you were looking for, rather than try to figure out how that answer is wrong, perhaps you should look for how that answer relates to what you're looking for.

What are you trying to find out about PS resistance training overall?
Zula110100100
#38
Nov26-11, 12:56 PM
P: 253
bodmas? I learned please excuse my dear aunt sally (Parenthesis, exponents, multiplication, division, addition, subtraction)
douglis
#39
Nov26-11, 04:20 PM
P: 148
Quote Quote by Zula110100100 View Post
In my opinion you need to change your angle of attack, the answer given for applied force obviously doesn't give you what you were looking for
The answer for the applied force gives exactly what he was looking for.He just don't like the answer!
sophiecentaur
#40
Nov27-11, 02:47 PM
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Quote Quote by Zula110100100 View Post
bodmas? I learned please excuse my dear aunt sally (Parenthesis, exponents, multiplication, division, addition, subtraction)
Brackets 'of' division, multiplication, addition & subtraction was what they gave me. Then, later, it became BIDMAS, with the I for Indices.
waynexk8
#41
Nov27-11, 05:34 PM
P: 399
Hi,

Just did the static test, and some others, they were all with about 80% and for 15 seconds on the leg extension.

Static hold half way up. Average muscle activation = 92.1.

Slow. Average muscle activation = 159.1.

Fast. Average muscle activation = 191.7.

Wayne
waynexk8
#42
Nov27-11, 05:40 PM
P: 399
Quote Quote by Zula110100100 View Post
The process that causes it to register more is the "force-applied" impulse being shorter time, more force(higher reading), but this will still be equal to the impulse of gravity if you average in the time that no force was applied. Just before it is moving up again,
Hmm, see you point, but this time when there will be no force, will be very small, about ??? Say we semented the whole .5/.5 rep of 1 second in a 100 parts, the rest time maybe just 1 part, so how and why do we need to average in something so small, as this will also be in the slower rep, but for a little longer.

Quote Quote by Zula110100100 View Post
it IS at a still start again. Any extra force applied to "get it going back up" from downward motion can be split between stopping it and starting again. The "stopping it part" is part of the downward rep.
Wayne
waynexk8
#43
Nov27-11, 06:00 PM
P: 399
Quote Quote by douglis View Post
I see the problem is a little deeper than I thought...
Yet again you fail to answer.

Quote Quote by sophiecentaur View Post
=41 if you follow the bodmas convention. Look it up. Anything X zero is zero.
To make it clear, you should use brackets.
After thinking about this, I make it 1, as what I did was x 80 x 0 the other way around, like this, 0 x 80, so if you x 80 by 0 it says at 80, but if you do it like this, 80 x 0, your timesing 0 by 80, but if you x anything by 0, its always going to be 0.

Not sure how you get 41 ??? But no matter, as Douglas did not even reply, it seems like he did not then understand the problem I was trying to get round.

Wayne
Zula110100100
#44
Nov27-11, 06:08 PM
P: 253
Static hold half way up. Average muscle activation = 92.1.

Slow. Average muscle activation = 159.1.

Fast. Average muscle activation = 191.7.
If the weight and time were the same, and they started and ended at v=0, then the force-applied impulses are the same in each. This shows that Average muscle activation does not directly correlate to fore-applied impulse. Do the same thing with different amounts of weight, each held for the same time, in the same position.

Also, is not power in mechanics, the combination of forces and movement ??? I thought power was the product of a force on an object and the object's velocity ??? As we all will agree that the fast uses more power, {even I can work that out with some simple equations} so if power is the of a force on an object and the object's velocity, does that not mean more force more power ???
Lets say we have a force of 1N, we apply that force at two velocities, one is 12m in 6s = 2m/s the other is 2m in 6 seconds = .33m/s, the power is 2(1) = 2watts for the fast one, and .33(1) .33watts for the slow one. The same force, different velocities.
waynexk8
#45
Nov27-11, 06:10 PM
P: 399
Quote Quote by Zula110100100 View Post
Yeah...I would say 41..and read it 40+(40*0)+1 = 40+0+1 = 41
Donít get that, but no prob.

Quote Quote by Zula110100100 View Post
I want you to do that expiriment because I think it will show that activity does not equal force, I think if you hold 20lbs for 1 second, it will be some amount that is less than double activity to hold 40lbs for 1 seconds.
Ok, get you a bit more, will do the tests tomorrow with a few different weights, to late here now,

Quote Quote by Zula110100100 View Post
In my opinion you need to change your angle of attack, the answer given for applied force obviously doesn't give you what you were looking for, rather than try to figure out how that answer is wrong, perhaps you should look for how that answer relates to what you're looking for.
Great, like you attack, yes I think itís great to change our angle of attack, and try and look at it from all different angles, and great youíre here, as someone very unbiased, and new to look at the debate.

Quote Quote by Zula110100100 View Post
What are you trying to find out about PS resistance training overall?
PS ???

wayne
Zula110100100
#46
Nov27-11, 06:16 PM
P: 253
Not sure how you get 41 ???
Because it is a well accepted convention that you do the multiplication before you do addition
so 40 + 40 x 0 + 1 you multiply 40 by 0 and have 40+0+1=41
waynexk8
#47
Nov27-11, 06:47 PM
P: 399
Quote Quote by Zula110100100 View Post
If the weight and time were the same, and they started and ended at v=0, then the force-applied impulses are the same in each.
Could not this be not true ??? As in my theory, when the fast reps are on their high peak forces, their accelerations, then on the low forces the decelerations, when they are on the low force decelerations, the slow force is still on its medium forces, and the medium forces of the slow reps, cannot make up or balance out the high peak forces, with their medium forces. The only way they could make up these forces, if the slow reps went on longer, but they do not.

Best I say this, as the faster reps will have what 12 v=0 starts and stops, too the slows just 2 v=0.
As the full debate is this; which rep/s use the most overall or total force or strength, using roughly 80% of the persons 1RM, and moving the weight 1m up and 1m down, 6 reps at .5/.5 = 6 seconds, moving the weight 12m in all, or 1 rep at 3/3 = 6 seconds, moving the weight 2m in all

As you know, an is the integral of a force with respect to time. When a force is applied to a rigid body it changes the movement of that body. A small force {slow rep} applied for a LONG TIME can produce the same movement change as a large force {fast reps} applied briefly, because it is the product of the force and the time for which it is applied that is important. The impulse is equal to the change of momentum. However both reps are done in the same time frame.


Quote Quote by Zula110100100 View Post
This shows that Average muscle activation does not directly correlate to fore-applied impulse. Do the same thing with different amounts of weight, each held for the same time, in the same position.
Will do.


Quote Quote by Zula110100100 View Post
Letís say we have a force of 1N, we apply that force at two velocities, one is 12m in 6s = 2m/s the other is 2m in 6 seconds = .33m/s, the power is 2(1) = 2watts for the fast one, and .33(1) .33watts for the slow one. The same force, different velocities.
Itís getting late here so not thinking straight, as its 1.30. But to accelerate a weight up, and thus to reach different heights in the same time, you would have to use more Newtonís of force to reach the higher high, or move it at a faster m/s ???

Wrote this earlier.
I can work out the power, learnt this from a site, {hope its right} as seen below and to be honest, I thought it would be basically as simple as this, was I wrong.
Calculate how much power/strength I would be used on both rep speeds. Distance weight of 91 kg moved 1.85 M.

To determine the force we will need to figure out what the weight of the barbell is (W = mg = 91 kg x 9.81 m/s = 892 kg.m/s or 892 N). Now, if work is equal to Force x distance then, U = 892 N x 1.85 m = 1650 Nm.

We can calculate that lifting a 91kg barbell overhead a distance of 1.85 m required 1650 J of work. You will notice that the time it took to lift the barbell was not taken into account.

Let us only add up the positive part of the lift.

Concept of power however, takes time into consideration. If for example, it took .5 seconds to complete the lift, then the power generated is 1650 J divided .5 s = 3300 J/s.

If it took 2 seconds to complete the lift, then the power generated is 1650 J divided 2 s = 825 J/s.

Wayne
waynexk8
#48
Nov27-11, 06:49 PM
P: 399
Quote Quote by Zula110100100 View Post
Because it is a well accepted convention that you do the multiplication before you do addition
so 40 + 40 x 0 + 1 you multiply 40 by 0 and have 40+0+1=41
Ok thx, will read that a few more times tomoorow, to late here now, half aslepp.

Wayne
waynexk8
#49
Nov27-11, 06:52 PM
P: 399
Why cant anyone asnswerr this please ???

1,
We both have a 100 pounds of maximum strength {or a machine is lifting} that we can bench press. We use 80% 80 pounds, I move the weight 1000mm in .5 of a second, I will be accelerating this weight for 60% for the ROM, {range of motion} of for the concentric rep, you will be moving the same weight in .5 of a second for only 166mm.

Question,
If I have moved the weight more distance in the same time frame, does that not that mean that I have used more force ??? {force and strength are the same I would have thought, but letís just go for force now} As even if you just count my acceleration its 600mm, that far morť distance than the slow.

2,
I bench press the same weight same distance of 80% {and this weight of 80% is important, as my maximum is only 20% more than my maximum} I lift at .5/.5 for 6 reps = 6 seconds covering a distance of 12m. The slow lifts at 3/3 for 1 rep = 6 seconds, covering a distance of only 2m.

Question, basically the same as the above.

As a force that causes an object with a mass of 1 kg to accelerate at 1 m/s is equivalent to 1Newton, if you move it futher in the same time from you have to use more force, Nís.

Wayne
douglis
#50
Nov28-11, 02:15 AM
P: 148
Quote Quote by waynexk8 View Post
Why cant anyone asnswerr this please ???

I bench press the same weight same distance of 80% {and this weight of 80% is important, as my maximum is only 20% more than my maximum} I lift at .5/.5 for 6 reps = 6 seconds covering a distance of 12m. The slow lifts at 3/3 for 1 rep = 6 seconds, covering a distance of only 2m.

Wayne
Wayne...you got your answer.What's clear is that you don't understand the answer or you don't like it.

In both cases the applied force is equal with gravity's impulse over 6 seconds....so it's the same.

40 + 40 x 0 + 1 = ???
Yet again you fail to answer.
Yes...I failed to answer so I asked my 6 years old son and told me it's 41.
sophiecentaur
#51
Nov28-11, 03:22 AM
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Quote Quote by waynexk8 View Post
Why cant anyone asnswerr this please ???

1,
We both have a 100 pounds of maximum strength {or a machine is lifting} that we can bench press. We use 80% 80 pounds, I move the weight 1000mm in .5 of a second, I will be accelerating this weight for 60% for the ROM, {range of motion} of for the concentric rep, you will be moving the same weight in .5 of a second for only 166mm.

Question,
If I have moved the weight more distance in the same time frame, does that not that mean that I have used more force ??? {force and strength are the same I would have thought, but let’s just go for force now} As even if you just count my acceleration its 600mm, that far morť distance than the slow.

2,
I bench press the same weight same distance of 80% {and this weight of 80% is important, as my maximum is only 20% more than my maximum} I lift at .5/.5 for 6 reps = 6 seconds covering a distance of 12m. The slow lifts at 3/3 for 1 rep = 6 seconds, covering a distance of only 2m.

Question, basically the same as the above.

As a force that causes an object with a mass of 1 kg to accelerate at 1 m/s is equivalent to 1Newton, if you move it futher in the same time from you have to use more force, N’s.

Wayne
You seem to want answers about this without having to make any effort to know the basics of Science or even primary School Arithmetic. We just can't help you on your terms. You have had many answers (the same answer put in different ways, actually) in a attempt to get the message over to you. Yet you refuse to give an inch (or even 2.54cm) so I am unsubscribing from this thread. I suggest you return the the pub / club / locker room and have your conversation with people who have no use for real Science but who just want an hour's worth of idle, anecdotal chit chat.
waynexk8
#52
Nov28-11, 07:55 AM
P: 399
Quote Quote by sophiecentaur View Post
You seem to want answers about this without having to make any effort to know the basics of Science or even primary School Arithmetic. We just can't help you on your terms. You have had many answers (the same answer put in different ways, actually) in a attempt to get the message over to you. Yet you refuse to give an inch (or even 3.54cm) so I am unsubscribing from this thread. I suggest you return the the pub / club / locker room and have your conversation with people who have no use for real Science but who just want an hour's worth of idle, anecdotal chit chat.
Hi sophiecentaur,

I don’t understand what you’re saying, to me the questions I asked on distance are just basic questions, and I put them down as plain as I can. I will give an inch or more. I am not from the pub or locker room.

I have made videos too which you have seen that you fail faster in the faster reps, thus why else would you fail if it was not because of you had used more force.

I bought an EMG that shows more muscle activity in the faster reps, = more force used.

I asked quite plain and polite questions on distance, and also proved with this little scenario that more force was used.

You place a piece of clay between your hands and the weight, THE CLAY WILL REPRESENT THE FORCE AND THUS TENSION FROM AND TO THE MUSCLES. The clay would be squashed MORE when doing the faster reps in the same time frame, YES ??? What you miss is that the high peak forces of the faster reps, can and do not make up or be balanced out by the medium forces of the slower reps when the faster reps are on the deceleration.

HERE IS WHAT A PHYSICIST ON ANOTHER FORUM SAID,

1. The first man uses the most force to do that, since he must push stronger for the weight to move a larger distance within the same time interval (acceleration is greater). Power is larger, energy is larger.

2. The fast man again. Since the time is smaller, there is more acceleration required and thus, higher magnitude of force. Power would be larger, energy would be larger.

3. Same as 2 since this is merely 4 times the work they are doing.


I honestly have not tried in any way to offend you, if I have I am all to sorry, that was not my intentions, I did say I would try to learn. What gets me is why you or some others can’t answer my distance questions ??? I dont get why people are getting uptight, all I ever wanted is to ask polite questions, and trieed my best to lay them out right.

If you can in my subjects, I would try to help you.


Wayne
waynexk8
#53
Nov28-11, 08:30 AM
P: 399
Think this may help the physicists here understand more, and no, this is not in any way to sound sarcastic, as I need to explain in more my laymanís terms.

Quote Quote by SumDumGoi View Post
Wayne,

As asked above, could you please clarify what your argument is? Are you saying that the maximum possible forced produced by a muscle will occur with faster vs. slower contractions?
How can I put this, say a muscle has a 100 pounds of force/strength to use up in a rep or in a set, the faster reps, I am saying that they use say a 100 of that total overall force/strength to the slow using say 70%, thus more total overall tension will go on the muscles, when doing the faster reps.

Does not my more distance moved in the same time frame, more EMG activity, muscles fail faster in the faster reps, and some more things show that.

Quote Quote by SumDumGoi View Post
Also, in regards to your physicist, what is his background in physiology? From a mathematical standpoint some of the things you have said are true.
Thank you, which ones please ??? Now we are getting somewhere.

Quote Quote by SumDumGoi View Post
However, when you are presented with what happens from a physiological standpoint your muscles would not be able to produce the increase in force required for the math to work. In other words there are physiological reasons why you cannot move a heavy weight very quickly and why when you move a light weight quickly muscular force is reduced. You need to apply the math within the constraints of muscle physiology. The person you are talking with needs to know both physics and physiology to understand the problem.
Well said. As because of the biomechanical advantages and disadvantages thought the ROM, the muscles cannot push up with full force like a machine could, but I donít mind keeping it as a machine, as it still holds true. I mean how can a machine push with a force a weight 1000mm to 166mm in the same time frame, and not use more total or overall force. Even if you just could the accelerations of the machine pushing fast, thatís say 600mm the machine has accelerated the weight to 166mm of the slow, and SOME here are trying to tell me that they use the same overall force accelerating the weight 600mm to 166mm ???

Your above examples violate what the muscle is capable of doing in the physiological world so they are not worth commenting on.
Yes I know that, but are just basic examples, I think all here know that ??? Big thx for your time and help.

Wayne
waynexk8
#54
Nov28-11, 08:50 AM
P: 399
Quote Quote by douglis View Post
Wayne...you got your answer.What's clear is that you don't understand the answer or you don't like it.

In both cases the applied force is equal with gravity's impulse over 6 seconds....so it's the same.
Add in the acceleration conponants please, How can the applied force be equal with gravity's impulse over 6 seconds all the time ??? Add in time and distance.

Or try and tell me how you move a weight 166mm and I move a weight 1000mm in the same time frame, and I accelerate for about 600mm of that distance. Your trying to tell me that you use the same force moving a weight far less disstynce in the same time frame



Yes...I failed to answer so I asked my 6 years old son and told me it's 41.[/QUOTE]

Letís see you try and prove this, with basic numbers

40 + 40 x 0 + 1 = ???

Is not 40 + 40 = 80 ??? Now we x 80 by 0, and whatever we x 0 by it will always be 0 right ??? So we are now at 0 right ??? So add 1 to 0 = 1 right ???

Wayne


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