by Robh » Thu Oct 16, 2008 8:05 am
[quote="Paul H"] I bought a pair last year and would be interested what Juerg's experience is with them. I dont believe what the Powercranks website says though. I havnt used them as much as I should but managed to build enough strength in my hamstrings to "rest" my quads when doing a thru & off and it seemed to work quite well but then I stopped using them. Ive started again though.
Paul,
I asked Juerg about the Powercranks In March. Heres his reply :-
Hallo Rob, thanks again for your question.
I use power crank here in my rehabilitation center daily with lot's of success.
The question as usual is on how do you measure success.
In a lot of discussion success is measure in seconds or added wattage or winning races.
Nothing against this.
For me success is to improve certain weak points in a patients or athletes situation.
Example:
I have a person , who has a knee or hip replacement , and after years of not using this side properly and even "
cheating" to avoid chronic pain, this person will keep this so called "bad habits" even after the fact , that the pain is gone and the ROM is fully restored.
In this situation it is amazing how independent pedals 9 Power cranks or manual treadmills ) will change the outcome , because there is no free ride for the weaker leg.
Yes "healthy " readers will argue , well that may be true for patients.
I could gently argue back :
Are you sure your left and right leg coordination is equal. You are using more than just the down stroke : and so on. I think at the right time using power cranks can be of a lot of values. People with "chronic" injuries ( overload on certain leg areas may benefit in assessing their symmetrical approach on the bike.
Than there is the never ending discussion on CNS ( Central nervous movement patterns )
What is this. Simple put "
As we learn a new motion in life ( as kids or as adults) we first go through this movement with either optical help , body feeling and sometimes ( as adults) even trying to analyze the full involvement of all muscles.
This takes part as a very clear thinking progress, starting to produce a memory pattern in our CNS and over our complicated way on learning movement.
As more often we go through this same motion as more "stable" this pattern will be and finally we may not even have to think anymore how to do it. ( it will give something like a reflex )
You can compare it with other examples.
An Ice hockey goalkeeper will first think how to pick up that puck in the right hand corner and over years and 1000 of shot's he just has this incredible reflex and we often have to ask ourself , how was that possible to pick that fast puck up. Well no time for thinking there, but over and over similar situations and the eye hand coordination just ends up as a reflex.
In cycling we could use RPM as an example: you bike since 25 years with an RPM of 60 - 70 and you do pretty good with that. Now the "wattage" believer may tell you to switch to 90 - 100 RPM perhaps and you will try , but it will be not as easy as it sounds. even though the motion is pretty close to the same. Nevertheless under race situation or in a situation where you have to work harder or you are tired you will find yourself back in this 60 - 70 RPM situation. Why smallest amount of "Thinking " Remember O2 is used in te brain as well and you 60 - 70 RPM may never reach your brain as it may be a pattern running just only over
the lower level of CNS the spinal cord.
Now if we add the power cranks to it we will have , depending on the "old" technique a completely different motion than on a normal pedal system.
We made a few years back lot's of tests with powercrank and were surprised, that road cyclist had much more problem to get the powercranks going compared to MTB guys.
Interestingly was that MTB guys , who were racing very smooth in the sand or on snow , had very little or no problem on powercranks at all and even the EMG pattern was very equal.
I had 2 guys , who immediately could ride powercranks from the first time they sat on it with very little problems.
So I think the main problem may be , that if we use pC we may have to start as kids to ride on them and once you have this pattern you can use this 360 turn also on normal pedals. If you ride since years you may be able to learn very fast to go on PC , but you may have a problem to integrate this motion under race or hard work situations, as you may fall back in your old motion pattern. The problem is , that it may in theory be much more efficient to use PC type of pattern, in reality it may take you years to switch over to this pattern as the main coordination you have.
I integrated the PC very early ( young age0 into our athletes program and once we had no difference in the EMG pattern we more or less quit using them , resp. if we use them once in a while there is no problem to use it , as it does not feel different at all.
I did a very nice mentor work with a sport student in Switzerland on PC ( resp smart cranks )
I think as well that the name power cranks is miss leading as it is more a question of optimal inter and intra muscular coordination and in fact you may actually use less power for a single involved muscle with power cranks than with normal cranks on the same wattage level, as you share the workload on more muscle groups than on a normal pedal.
Can you push higher wattage.
We as well tested this.
Short term like in a wingdam test yes you can push more wattage over a few seconds.
In a full FaCT test no , the maximal wattage as well the LBP HR was in our cases more or less the same ( with daily fluctuation as in any test.
Was the VO2 different. No not at all .
Does this makes sense.
Well in a good athlete yes. If you test in a beginner the VO2 is lower with PC and the wattage is lower, due to the fact , that it is a very specific limitation in the hip flexor group and the HR , as well as the lactate and VO2 will not really react , due to the limitation in one single group.
Interestingly is , that as less wattage you will add to a beginner using PC as harder it is for that person to actually bike. the same is true for more resistance and for too slow RPM and too fast RPM.
They spontaneously will choose a very comfortable ( not coo-ordination challenging RPM) and they will choose to sit upright on the bike ( no aero position ) due to the incredible difficult task for the hip flexor to contract in this shortening position.
Sunmmary:
Athletes with a high degree of motivation can benefit in the winter month or during stages of injury from PC to use them to maintain an equal and balanced muscle activity.
I am not sure, whether this will translate in the above way of measuring success ( Time and wattage) but it may help to prevent certain injuries which than allow for more regular training , which than may end up in a better performance, thanks to PC or perhaps better thanks to understanding the fact, that lot's of intervention we use in sport and life are needed to maintain a balance in our body and therefor will help to perform better.
You could ask the same question in a nutritional discussion.
Do I need protein to be faster in this upcoming TT.
Answer may be no. But: if you avoid protein you will have lot's of problem with your body and therefor it has something to do with the performance in that TT.
I see far to many "simple" answers and approaches in using one or the other equipment to improve performance
. I think it has to be looked upon the overall picture.
Last example as you started this nice discussion lot's of month back :
IHT or altitude training.
The investment of an altitude equipment for 99 % of the readers is money wrong spent.
Most of us could benefit simply by just going out and ride our bike , because we are far away of getting a limitation of improvement we just riding our bike.
The little theoretical improvement in a TT for us cause by placebo or the altitude tent or equipment is so small, that it is not worse the thought on it, but it is still fun to read all the research and promises we get from the industry.
So as long you have fun and you have not money to throw around you need simply a bike with 2 wheels and pedals and breaks and up you go.
You combine that with a smart way of understanding the basic rules of your bodies reactions and you can enjoy life and motion on your bike. Work on your personal improvement and forget the race for comparison as you don't need to proof anything to anybody but to yourself in the way you enjoy your health and ability to move.
Well lot's of people may not agree with this philosophy and will argue it does not work in high performance.
Many years later I am proud together with Herb to be able to say , that we never had a mass production of athletes , but the few we coached together all made it to their personal best and that was in nearly any case a top placing in the country or even in the world and this with clean no drugs approach at all.
Does this count ?
No I am much more proud on the many "small" fishes we have in our clinic , who learn to enjoy again an active lifestyle and working on teh personal best.
Mr. Miller , who is back in the pool after a heart attack and enjoys swimming.
Mr. Smith , who is back with 2 artificial hips and running with his sled dogs.
Mr. "Do little" who decided after his prostate cancer to take up running a 1/2 marathon.
This are the real improvement and it makes me more and more smiling , when I read argumentation in so called pro forums on wattage and PC and what is better or not , missing all the points of where and when do we can enjoy and add ideas and possibilities to our workouts. Thanks Rob for your question and have a nice easter weekend with your family. Juerg