Where does power come from?
- Thread starter Piotr
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Uh, I said nothing about energy. I was only talking about force (effort in a direction) summed to the whole.Fday said:
The term I wanted to use was power because that is what is needed but you do not comprehend what that is and want to go with sthregth(X).Fday said:
You appear to be the only one who does not understand it or can repeat it.
Seeing as though stregth(X) is not definded/accepted it is hard to discuss this.Fday said:
From everything I have understood you to say about stregth(X) it is only a linear value. I will have one stregth(X) for my quad, one strength(X) for my calf, etc. And you think that is easier than getting on a trainer and riding all out for one hour?
Speed is not what counts. There is so much more to it than that.
Correct, and out of all of those the interactive coach is the best way to improve. They should look at each individual and develop a plan for that individual. They will probably use some of the books that an individual can purchase themselves and other tools at their disposal.Fday said:
Books are good but they are wrtitten for the masses. I have read some of these books. I have read articles by Andy. But some how I think if I met one on one with Andy he would have me do things at least a little bit different, because he would adapt it to me.
Tools, like your product, powermeters, etc. are only that, tools. They in themselves do very little to improve performance. A person could slog on the flat on your product at a cadence of 60rpm for the entire ride and be fine with your product. Somehow I doubt a good cycling coach would allow a person to turn that slowly for that long.
I am one that does not have a PM. I have no clue what my FTP is. I have a trainer that provides me a number that I use for comparison purposes. My cyclocomputer has a number that for the most part is worthless but I compare between rides.
However, as a result of these I have determined that the force (either up or down) I apply on the peddals is not my limiting factor. For me it is a negative factor. I have lowered that force, increased the number of times I do it in a minute, and have improved my performance.
There are a lot of product/opinion out there that are complete BS. Others one needs to look at the value returned from the product. And this is where I think a good coach is well worth the price paid.Fday said:
To think a person would spend $1,000US for a product that has limited use when that $1,000 can be spent in other places and return much more baffles me all the time. But it is their choice.
this isn't quite correct...Fday said:
a) if you wanted to increase power you would actually want decrease the time (it't per unit time... time is on the bottom so decreasing time increase the resulting power)
b) yes you cannot decrease the unit of time but you can decrease the time i.e. you can go from 1 sec to .5 sec... per rev/per muscle contraction or in cycling talk increase cadence... and this would increase the power and the torque (the force you press on the pedal) could stay the same... if you increase the cadence/angular velocity (decrease the time per rev) enought you can actually decrease torque and still be increasing power... but in doing this (increasing power which decreasing torque) wuold still require more oxygen delivery and utillization.
that's the point... forget about how strong the muscle is, what is most important for most kind of cycling baring sprints to the kilo... is getting oxygen to your muscles and your muscles utilizing it.. i.e. your aerobic abiilties... anaerobic abilities can be very important to strategically, but what is compulsary is very good aerobic abilities... your aerobic abilities are your ticket to get on the field but your anerobic abilities give you more moves or cards to play in the actual game...
Ugh, it is math. You can increase one side or decrease the other. It doesn't make any difference. I was using what I thought was convention, that is, unit time.doctorSpoc said:
Anyhow, you didn't read what I said before. While it is possible to decrease torque to increase power if one increases cadence more, it is not possible to decrease muscle force and increase power. It takes a larger muscle force increase to increase the cadence than one saves in reducing pressure on the pedal. If you have evidence to the contrary I would love to see it. I submit it doesn't exist because it is impossible. The work done on the pedals comes directly from the muscles. If more work is being done at the pedals, then more work is being done by the muscles and at higher cadences there is more internal work and other losses to overcome.
Yes, aerobic endurance is important, but so is muscle strength. It takes improving both to improve in an endurance eventl like cycling.
Frank
Actually, let me modify what I said above. It is possible to decrease muscle force and increase power, but not my simply increasing cadence to reduce pedal forces. Pedal forces say little about internal muscle forces. The way to reduce muscle force to increase power is to improve the pedaling dynamic to increase efficiency. That way the rider gets more work/power out of the same muscle effort. Wonder how one might do that?Fday said:
Anyhow, I stand by the general concept, if efficiency doesn't change it is impossible to increase power without increasing muscle force.
you are dead wrong... and yes it is math... see belowFday said:
Power = Torque x Angular Velocity
= torque x meters/second = torque x distance/time
i'm not going figure out the units.. but lets say power = 100, we'll say that distance = 1 meter for simplicity (really long crank arms
)so we have an equation that looks like this...
100 = torque x 1/time
if torque is 100, angular velocity is 1m/s --> 100 = 100 x 1/1.0
if torque is 50, angular velocity is 2m/s --> 100 = 50 x 1/0.5
- same power half the torque!
now lets say we want to increase power to say 200
i could do this... torque = 50, angular velocity = 4m/s --> 200 = 50 x 1/0.25
- twice the power half the torque!
i have shown with math that you can absolutely decrease torque and if you increase angular velocity (cadence) you will increase power...
you are right it is just math.. it is math that has shown you are absolutely wrong!
you know a few formulas but you don't understand them... you are confusing a whole lot of things.. have you ever heard of a little thing we like to call mechanical advantage? do you know how it works? why we use gears? you seriously need to do some more reading.. like they say a little knowlege can be a dangerous thing..
And how do you measure the internal muscle forces with you Strength(X) formula you want us to adapt to?Fday said:Actually, let me modify what I said above. It is possible to decrease muscle force and increase power, but not my simply increasing cadence to reduce pedal forces. Pedal forces say little about internal muscle forces. The way to reduce muscle force to increase power is to improve the pedaling dynamic to increase efficiency. That way the rider gets more work/power out of the same muscle effort. Wonder how one might do that?
Anyhow, I stand by the general concept, if efficiency doesn't change it is impossible to increase power without increasing muscle force.
There is so much more to this then prue stregth.
Another example I think you will again choose to ignore. However, when rowing in college probaly our best rower was the "weakest" person on the varsity crew. He had no arms, legs, back, stomach. He was always at the bottom in all of our "strength" drills. He could not pull and erg time to get him in the #1 novice boat.
But he was the best skull, and if you were is a dual or a quad with him he could punish the boat. Generally in an eight he met his match going up agaist seven other oars. But you could still tell he there if he wanted to prove a point. He had all of those internal muscles working in the right direction.
He was also a very good cyclist. We did not do and phisiological tests but I am sure if we had he would have a very high FTP.
I think a lot of power comes from our parents. We need to have a strong heart, large lung volume, excelent gas transfer between the lungs and blood, and stong muscles.
Do you want to learn or just teach us half brains? Are you really that hurt with being called stupid?
I don't understand. I agree with your analysis here completely. It is incomplete though.doctorSpoc said:you are dead wrong... and yes it is math... see below
Power = Torque x Angular Velocity
= torque x meters/second = torque x distance/time
i'm not going figure out the units.. but lets say power = 100, we'll say that distance = 1 meter for simplicity (really long crank arms
so we have an equation that looks like this...
100 = torque x 1/time
if torque is 100, angular velocity is 1m/s --> 100 = 100 x 1/1.0
if torque is 50, angular velocity is 2m/s --> 100 = 50 x 1/0.5
- same power half the torque!
now lets say we want to increase power to say 200
i could do this... torque = 50, angular velocity = 4m/s --> 200 = 50 x 1/0.25
- twice the power half the torque!
i have shown with math that you can absolutely decrease torque and if you increase angular velocity (cadence) you will increase power...
you are right it is just math.. it is math that has shown you are absolutely wrong!
you know a few formulas but you don't understand them... you are confusing a whole lot of things.. have you ever heard of a little thing we like to call mechanical advantage? do you know how it works? why we use gears? you seriously need to do some more reading.. like they say a little knowlege can be a dangerous thing..
Where you are wrong is you assume that because the torque goes down the muscle force and power necessary to achieve that torque would go down. If that were the case we would all be riding at cadences of 150 or 200 or 250 or so. We can't because it takes too much energy, regardless of how much or little force is put on the pedals.
Like you said, a little knowledge can be a dangerous thing. Well not dangerous here but certainly can lead you down the garden path to wrong conclusions. Regardless of how you do so, if you increase power, the muscle forces and energy expenditure have to increase. There are no two ways about it.
Internal muscle forces can be measured in a several ways in real people. One directly and one indirectly. In the laboratory they can be measured by attaching strain gauges to tendons, etc. This is rarely done to real people.vadiver said:
There are probably some other methods also. It is not my area of expertise. Another method used in cyclists looks at the end result of a bunch of muscles together, that would be by using force pedals which measure the amount and direction of the resultant force but it does not actually tell you what is going on in each muscle alone or together because it doesn't measure losses or inefficiencies that occur before the force is applied, as I mentioned before.Anyhow, the direct method is to insert a small needle into the muscle and measure the change in internal pressure. This doesn't give an actual force but it correlates extremely well to actual forces. The other and more usual way is to measure EMG activation of the muscle using skin electrodes. The stronger the EMG signal the stronger the muscle contraction. Again, pretty good correlation and pretty easy to do in the laboratory.
There are a couple of places doing some studies on my product who are looking at this very thing (EMG activation and changes that occur in both runners and cyclists from using the product) right now.
like i said you need to read up on what mechanical advantage is and how it works... think pliers, think tweezers... if power goes up then yes absolutely energy expenditures go up, but not necessarilly muscle forces... there is more than two way about it... to increase power you can keep force the same and increase cadence, you can leave cadence alone and increase force or you can increase both cadence and force...Fday said:
this is grade 7-8 physics... Work = Force through a distance and we cannot reduce the work/energy expenditure (conservation of energy and all that..)... but in all cases.. tweezers, pliers, and bicycle gearing you reduce the force necessary and apply it through a longer distance so in the end you are actually doing the same work even though you are applying a much reduced force.. at the same power in a smaller gear your feet travel a greater distance (more revs...each rev represents a distance equal to the circumferance of the circle that goes though the pedal axis) per unit time than in a higher gear... as i said this is grade 7-8 physics... if you don't understand this, good luck understanding the more complex stuff..
W = Fxd
100 = 100x1
100 = 50x2
100 = 25x4
- reduced force.. greater distance applied through --> same work, same energy
he's actually right.. force is not zero the force is tangental to the crank... displacement for one revolution is zero (effective work might be zero.. but not likely since you likley put more force into the down stroke than lifting?).. but the distance i travel for one revolution is the circumference of my crank arms... if i do a ride starting at home and end up at home (total displacement is zero) i still exerted some ave force for whatever distance i traveled over and accomplish whatever work or exerted whatever force at a velocity of whatever with an average power of whatever... same is true of a pedal rev... sure i end up where i started but my pedal still traveled the circumference of the circle that goes though my pedal axles and applied whatever force for the duration... the fact that the total displacement is zero is not really a factor.vadiver said:
Sorry, it goes beyond grade 7-8 physics. I wasn't taught physics til high school. Overschooled I guess.doctorSpoc said:
Here is what you are missing. How much energy it takes to make the legs go around. Look at the pumping action of the thigh. It is accelerating up to a maximum speed then decelerating to zero the back to a maximum speed and back to zero twice a rotation it does this acceleration and deceleration. The thigh weighs perhaps 20 lbs. If you increase the cadence, not only does the thigh have to accelerate to a higher speed but it has less time to get there. The energy requirement to do so increases with the square of the cadence. The power required to do this increases with the cube of the cadence.
Now, where is this power coming from. Some will say it is coming from the other leg, one is going up while the other is going down. Well, that balances the potential energy but it doesn't balance the kinetic energy changes because both legs are accelerating and decelerating at the same time, just in opposite directions. Since this is a scalar and not vector number these equal but opposites do not cancel out but add together. It is not 7-8th grade physics but it is basic college physics.
Now, where is the energy coming from to do this? It can only come from one place, the muscles, the same muscles pushing the bike forward. Do the energy analysis. It is tedious but straight forward and then get back to me with what you find.
cheers.
Ok..Fday said:Internal muscle forces can be measured in a several ways in real people. One directly and one indirectly. In the laboratory they can be measured by attaching strain gauges to tendons, etc. This is rarely done to real people.
So we can measure each muscle and add them all up to get our strength(X). I would suspect there are a lot of muscles that are being used in each pedal stroke. We will then analyze the data and determine what muscle we should focus our training on. The only problem is we come back to the study of 1 vs 6000 reps.
Question. This is only the one time strength, not the 6000 rep strength, correct?Fday said:
Why do you not have a study conducted to test FTP of Elite/CAT1/CAT2/etc. riders?Fday said:
No, these measuring systems can be used for multiple repetitions. The entire ride could be analyzed and watch how the muscle fatiques over time or how the coordination changes with time. It could be done for one rep or 10000 reps or anything in between, whatever is enough to answer the question the investigator is asking.vadiver said:
I don't have the study you ask about FTP for various levels because I don't care about that. I am sure it exists. I just don't think it is particularly interesting. People are as strong as they have trained usually. My interest is in making people better whatever their current level and in figuring out how to best do that.
Frank
It would take one electrode for each muscle being measured.vadiver said:
It would be easier to measure power for an hour but you don't learn as much. If you want to know about muscle activity you need to measure it.
Marketing what? Everyone cannot know everything. There are others here who can answer your question I am sure.
Right, this is what my question was. Since I am not am MD I do not know. How many muscles are used for one pedal stroke. How many muscles are in the leg alone, at least eight.Fday said:
I do not care about the muscle strengh in my left pinky, I just want it to relax so it does not use as much energy.Fday said:
Do a study, post a 40% increase, and hope nobody questions it.Fday said:
Fday said:
And, failing miserably.
i *challenge* you to show me one person who has improved from average as you previously described (i.e., 2nd or 3rd cat cyclist) and gained this 'mythical' (or perhaps better described as b@ll@cks) 40% power. With their permission send me their Power Tap files to validate the improvement.
Ric
