wattbike help

jonod777

So my gym has just got some wattbikes in and i wood like to know how i can use them to help get ready for my first bike race next month

Herbsman

What bike?

MarksMintness

They look amazing bits of kit, company is based in Nottingham I believe. Lots of stats/data about your pedal stroke/power etc.

Herbsman

I doubt that using a Wattbike would help much in the short term. However, in the long term it could be of some use to you. Read up on training with power. There are numerous threads on here and there's a book called Training And Racing With A Power Meter you could read.

Eddy S

Take a look at the Training Guide on the Wattbike site. This will give you an idea of how to use it and what the data means.

The long-term plans are for sportives and triathlon but you might get something out of them depending on where you need development.

Short-term, you can use it to keep doing training sessions if you can't/won't ride due to bad weather - no excuses for missing any training now. Mine get used all of the time - I do either sessions/intervals that are intended for rollers/turbo or I can replicate some of my specific road sessions.

jonod777

Eddy S wrote:

Take a look at the Training Guide on the Wattbike site. This will give you an idea of how to use it and what the data means.

The long-term plans are for sportives and triathlon but you might get something out of them depending on where you need development.

Short-term, you can use it to keep doing training sessions if you can't/won't ride due to bad weather - no excuses for missing any training now. Mine get used all of the time - I do either sessions/intervals that are intended for rollers/turbo or I can replicate some of my specific road sessions.

i need to look into getting a powertap hub for my bike then

bahzob

Wattbikes are a good piece of kit, than can complement road training.

In terms of power measurement they are very reliable.

Also they provide a unique real time view of your pedaling action. Used wisely this can help make your stroke more efficient with very real performance improvements.

It's described here http://wattbike.com/uk/guide/cycling_te ... hapes_mean

Which sort of explains but it's this is the sort of the thing you need to try for real to appreciate. It can be very illuminating.

The main drawback with them (at least early ones, not sure if since fixed) is limited range in terms of bike setup, in particular aggressive TT positions, which is a particular shame because otherwise they are perfect for TT training.

liversedge

They also have a really nice road "feel". I tried one out at Hillingdon a couple of years ago and was really impressed. If my gym had one I would be over the moon. Its made by the same folks that make the Concept II rower.

Alex_Simmons/RST

bahzob wrote:

Wattbikes are a good piece of kit, than can complement road training.

In terms of power measurement they are very reliable.

Also they provide a unique real time view of your pedaling action. Used wisely this can help make your stroke more efficient with very real performance improvements.

It's described here http://wattbike.com/uk/guide/cycling_te ... hapes_mean

I don't disagree that they are good kit (they are), however the pedal charts are not a lot more than a curiosity, and have bugger all to do with a rider's efficiency or performance.

bahzob

Alex_Simmons/RST wrote:

bahzob wrote:

Wattbikes are a good piece of kit, than can complement road training.

In terms of power measurement they are very reliable.

Also they provide a unique real time view of your pedaling action. Used wisely this can help make your stroke more efficient with very real performance improvements.

It's described here http://wattbike.com/uk/guide/cycling_te ... hapes_mean

I don't disagree that they are good kit (they are), however the pedal charts are not a lot more than a curiosity, and have bugger all to do with a rider's efficiency or performance.

We have argued about this before. You have your opinion and are entitled to it. However it that doesn't make it true.

Its basic physics that you should be aiming to maximise the efficiency of any mechanical process.

You get advice on this in training guides, its in the form of "pedal in circles", "kick through the bottom" etc. OK but pretty limited without a means to measure it.

Wattbike is the only (? there may be more, don't know of them) that gives riders real time feedback on the how efficiently or otherwise they are pedaling.

If you use one you can relate the pedaling training advice much more easily to what you are doing.

I use one 3-4 times a week and am quite sure it has improved my effective power. Its actually not hard to demonstrate, if you pedal "badly" according to the polar view then you tire earlier and the fatigue tends to be limited to certain muscle areas, typically front of the thighs as you smash the pedal down. Conversely focusing on maintaining a "good" form helps maintain power through tough intervals and the end session fatigue is more whole body.

Further I have found I become far more aware of how all the various parts of the body contribute towards developing and maintaining power.

As I said in my first post you really need to try one for real to see/experience this.

liversedge

The computrainer spinscan function does the same realtime feedback. I would love to see it equated to muscle recruitment. I have small vestas medialis and don't kick over the top, a riding buddy of mine does and has different muscle toning. We are different. But is that because of genetics or a pedalling style?

Personally, I think there is some value in assessing the pedalling stroke, not everyone has good form naturally.

Alex_Simmons/RST

bahzob wrote:

We have argued about this before. You have your opinion and are entitled to it. However it that doesn't make it true.

It's not my opinion. It is the outcome of considerable research on the subject, which was neatly summarised by Jim Martin in this presentation:
Myth & Science in Cycling: Crank Length & Pedaling Technique

bahzob wrote:

Its basic physics that you should be aiming to maximise the efficiency of any mechanical process.

No, in (competitive) cycling we should be aiming to maximise performance. Maximising efficiency is a red herring. The fastest car is a race is not the one with the best fuel economy. If we had the aim of maximising efficiency, we'd all be pedaling at 60rpm, but we don't.

bahzob wrote:

You get advice on this in training guides, its in the form of "pedal in circles", "kick through the bottom" etc. OK but pretty limited without a means to measure it.

Which are mythological ideas starting from a false premise that such things improve efficiency (or effectiveness), when in fact such pedaling actions recruit inherently less efficient muscle groups. Reference the Korff study in above link.


The final point to make is that none of these machines (Wattbike, Computrainer, Velotron) actually report independent pedal forces around the pedal stroke, they are only inferring it. They can't since they are measuring combined forces from cranks which are connected. The only way to perform such analysis is with independent force measurement pedals (of the kind used in the studies referenced in the paper above).

And yes, I have used them. I even ran an indoor training centre with Computrainers, have my own, and also consulted to others with Wattbikes. A few Velotrons, but not as many (they are much more expensive).

Alex_Simmons/RST

liversedge wrote:

The computrainer spinscan function does the same realtime feedback. I would love to see it equated to muscle recruitment. I have small vestas medialis and don't kick over the top, a riding buddy of mine does and has different muscle toning. We are different. But is that because of genetics or a pedalling style?

Personally, I think there is some value in assessing the pedalling stroke, not everyone has good form naturally.

My best ever form coincided with the "worst" ever spinscan numbers.

ric/rstsport

Didn't the AIS also report that the Wattbikes weren't reliable in terms of their measured power output, i.e., they differed between units?

Ric

Alex_Simmons/RST

Ric/RSTSport wrote:

Didn't the AIS also report that the Wattbikes weren't reliable in terms of their measured power output, i.e., they differed between units?

Ric

It was South Australian Sports Institute (where AIS cycling is based), although to be fair I think Wattbike might have improved since then, although I have nothing to validate that thought. The reports of WB accuracy out of the AIS improved after Wattbike became a sponsor of CA.

It's a very good ergo trainer, I'd certainly recommend them. But like many tools, it provides some "features" that are either misunderstood or are gimmicks.

Way back when they first came out I had a conversation about the pedal power data/charts with the sports scientist who developed the original Wattbike design. He agreed with me that the marketing material about the use (and usefulness) of the pedal charts/technique was a little, well, off the mark. But the ideas are so entrenched and pervasive that to say otherwise in the land of cycle equipment marketing is probably heresy. Bit like saying the weight of a bike wheel isn't important.

siamon

That crank length and pedaling technique report is a real eye opener. Thanks for posting it!

Alex_Simmons/RST

siamon wrote:

That crank length and pedaling technique report is a real eye opener. Thanks for posting it!

I know.

But heck, one shouldn't let the facts get in the way of a good story.

Mind you, I am far less well versed on the issue of pedaling matters than one of my RST Sport colleagues, who recently published another paper on the impact of Q-factor and has immersed himself in the issues.

Herbsman

WTF is this I don't even

bahzob

Re Efficiency. Perhaps I wasn't clear. I was using the term in the sense of mechanical efficiency which is defined as measured performance/ideal performance. To make your car go fastest you will be attempting to maximise this, through for example aerodynamics, tyre tread, engine materials etc.etc. The essence of F1 is that winning requires the optimal trade off between mechanical efficiency and course conditions.

wrt the topic at hand everyone, I think, accepts that in order to maximise your efficiency in this sense you need to have a correctly setup bike and be seated in the ideal position.

The issue seems to be whether, assuming the above to be the case, you can further improve your efficiency through how you pedal. I remain of the opinion that you can. Indeed I would say you can only really be sure the bike setup is correct by taking the pedaling action into account. I would have said this is most obviously the case in time trialling but has more general application.

Re the Jim Martin presentation.

The first half is mainly concerned with crank lengths.

The Korff study seems to have been conducted by telling the participants how to pedal. I've already said in previous posts that is a flawed method. A typical study that involves proprioception will use visual/auditory feedback mechanisms as these are easier for the brain to relate to its inputs. Example is if you tell someone to lower their heart rate they will often find it hard. If instead you just display an image of some sort showing the HR or simply amplify their HR so they can hear it they will find it a lot easier.

The key thing about the Wattbike is that it provides real-time feedback on how you are pedaling analogous to the HR feedback above. Using this it is possible to determine for yourself how to pedal best. This will be considerably more sophisticated than the simplistic "push", "pull" that Korff was trying and it will vary according to power output and situation (seated/standing, climbing/TT etc). It is interesting to note that notwithstanding its faults the Korff study did in fact show differences between styles, the problem being that what was most "effective" was least "efficient".

I would suggest that the more efficient pedal action that you can develop via feedback like the Wattbike provides is because it allows you to learn how to trade off factors like effectiveness and efficiency. Of course it works precisely because you don't have to think in these terms. The action you develop isn't "push" or "pull" or "circle", its a bit of each (e.g top thigh pushes, lower thigh pulls while knee is circling).

The Martin study isn't very clear on its methodology. It supports my view that it is possible to learn to pedal better (as happened for the untrained cyclists). However its does not say how the trained cyclists were expected to learn???? Were they just told to pedal better? Further the results seem a bit bizarre. The slide comparing active men with trained cyclists seems to show that over the 4 days the "trained" cyclists not only got worse but by day4 the "untrained" cyclists actually recorded better W/kg figures????? Weird.

It also seems, as some other studies here, to only have looked at max power which is of limited use. Intense max effort bursts are by their nature the hardest to undertake while simultaneously attempting to monitor your pedaling action. They are also unrepresentative of most cycling activity and use atypical muscle groups/resources. I appreciate that max power tests are easiest on testers and subjects in terms of getting things done. But really it would be more helpful if they used a more representative test like a 5-20 minute interval.

Alex_Simmons/RST

bahzob wrote:

Re Efficiency. Perhaps I wasn't clear. I was using the term in the sense of mechanical efficiency which is defined as measured performance/ideal performance. To make your car go fastest you will be attempting to maximise this, through for example aerodynamics, tyre tread, engine materials etc.etc. The essence of F1 is that winning requires the optimal trade off between mechanical efficiency and course conditions.

No, efficiency is a measure of energy loss in a system. No more or less.

In a car it's how much energy reaches the wheels versus the energy content of the fuel burned.

In cyclists it is the energy reaching the cranks as a proportion of energy metabolised.


Ideal performance may or may not have anything to do with efficiency.
e.g. the fastest car in a race is rarely the one with the best fuel economy.

If you are going to use a tool to help you improve performance (physiologically), then focus on improving the most important (physiological) element of performance - sustainable power output.

Last year at a UCI Road World Cup I had my best ever performance in a TT, highest all-time sustainable power for a bit over 30-minutes (actually I had a cracker of a race block with other great results as well). Yet my pedaling action according to these devices was the worst it had ever been. So glad I didn't fall for the pedaling BS, and instead concentrated on what was important.

liversedge

With the greatest of respect Alex, that's n=1. More importantly, how do you know that with a different bike fit, and training to recruit more muscle fibres with a different pedal stroke that you might not perform better? You don't, because you haven't tried.

I do not believe that we can say spinscan etc works either, but equally, we cannot say that it does not.

ric/rstsport

liversedge wrote:

With the greatest of respect Alex, that's n=1. More importantly, how do you know that with a different bike fit, and training to recruit more muscle fibres with a different pedal stroke that you might not perform better? You don't, because you haven't tried.

I do not believe that we can say spinscan etc works either, but equally, we cannot say that it does not.

we *can* say spinscan doesn't work, simply because it doesn't measure what it purports to measure.

if you want to know how you pedal, then you need force instrumented pedals.

Alex_Simmons/RST

liversedge wrote:

With the greatest of respect Alex, that's n=1. More importantly, how do you know that with a different bike fit, and training to recruit more muscle fibres with a different pedal stroke that you might not perform better? You don't, because you haven't tried.

I do not believe that we can say spinscan etc works either, but equally, we cannot say that it does not.

With the greatest respect, you have absolutely no idea what I have or have not tried. When I learned to walk and ride a bike again from scratch after an amputation, I can assure you, I tried a LOT of things. As did my bike fitter, Steve Hogg.

I was simply pointing out that SS is providing information of very limited value wrt performance, yet people are claiming it to be of substantial value and that one needs to achieve a certain type of pedaling profile in order to perform better.

I'll let people in on a little something about SS on a CT that no one tells you.

If you ride a .crs file on a CT using a pedal "technique" that changes the SS numbers - according to the CT you can ride at a (significantly) different speed for the same reported power. Wouldn't that alone make you just a little suspicious?

bahzob

Sorry Alex but you cannot just come up with a definition of efficiency then decide ipso facto that anyone who does not agree with this is wrong.

Your view that efficiency is the energy loss in a "system" is too narrow.

It is perfectly normal to also apply the concept to the components of the "system" with the view that improving their efficiency will also improve the "system's" total efficiency.

Indeed this is standard practice.

You know it is because you apply it to factors such as aerodynamics and bike kit.

This particular debate focuses on the transmission efficiency downstream of power output. To make an analogy with a car it is the various components that convert the engine bhp to actual power on the road, like gear box, prop shaft, tyre compound composition etc. It's standard practice btw when you have a car tuned that you get 2 power figures, one for the power at the engine, the other (by definition lower) the actual power applied to the road. This is an efficiency measure, pure and simple.

I have to assume that you agree it is perfectly sensible to talk, in the same way, about the efficiency of the actual bike components in this context. A rusty chain is less efficient than a well oiled one.

And I have to assume you agree it is perfectly sensible to talk about the efficiency of bike set up in this context. e.g. moving the seat forward/back up/down will have an effect.

So I remain sure it is also perfectly sensible to talk about the efficiency of the pedal action in this context. On a trivial level this is obvious. If you try to pedal by pushing down with maximal force when the pedal is vertical you will tire quickly and not go very fast. It is a huge leap of faith imo to assume that because people don't pedal that way they necessarily pedal in the most efficient way possible.

As I indicated in my previous post the material you linked supporting your case is pretty flawed

I rather believe the evidence of my own eyes. If your view is correct then the cyclists in this video are pedaling in the most efficient way possible. Hard to believe and very sad if its the case imo.

http://www.youtube.com/watch?v=VSdv7hRETe4

ric/rstsport

<sigh>. the definition alex uses for efficiency is the definition of efficiency. you only have to check any text on physiology to understand this.

you're wrong.

Herbsman

liversedge

Ric/RSTSport wrote:

liversedge wrote:

With the greatest of respect Alex, that's n=1. More importantly, how do you know that with a different bike fit, and training to recruit more muscle fibres with a different pedal stroke that you might not perform better? You don't, because you haven't tried.

I do not believe that we can say spinscan etc works either, but equally, we cannot say that it does not.

we *can* say spinscan doesn't work, simply because it doesn't measure what it purports to measure.

if you want to know how you pedal, then you need force instrumented pedals.

Well, I think the broader discussion is about pedalling, muscle recruitment, efficiency and performance. The SS numbers may or may not be accurate, I think that is a separate topic. I said "spinscan etc" to refer to all types of pedal analysis, since we we're discussing the wattbike, some of which I think will be coming with vector too?

I'm not precious on this, but you two seem very certain of your position and I personally don't feel you have explained why that is the case. But life is too short and the sun is shining

ric/rstsport

can we swap. it's hammering down here :-(.

i'm short on time (hence my short replies) this week. but there's a whole load of research by jim martin, the other bloke whose name escapes me at the moment (that's bugging me; the biomechanist in the usa) who looked at pedalling forces, through to stuff by coyle. it basically says what alex is suggesting

Alex_Simmons/RST

bahzob wrote:

Sorry Alex but you cannot just come up with a definition of efficiency then decide ipso facto that anyone who does not agree with this is wrong.

My apologies for referring to one of the most fundamental and accepted laws of nature when using the term efficiency.

http://en.wikipedia.org/wiki/Energy_con ... efficiency

Alex_Simmons/RST

bahzob wrote:

You know it is because you apply it to factors such as aerodynamics and bike kit.

A change in aerodynamics such as a disk wheel might change the speed - power relationship, but not efficiency. You are getting the same amount of energy delivered to the wheel for the energy metabolised.

Alex_Simmons/RST

bahzob wrote:

I have to assume that you agree it is perfectly sensible to talk, in the same way, about the efficiency of the actual bike components in this context. A rusty chain is less efficient than a well oiled one.

Yes, one can talk about the energy losses associated with using certain equipment, that is normal. On a road bike, typical drivetrain losses are of the order of 2-3%.

bahzob wrote:

And I have to assume you agree it is perfectly sensible to talk about the efficiency of bike set up in this context. e.g. moving the seat forward/back up/down will have an effect.

I think it is perfectly reasonable to talk about the effectiveness of different bike set ups, and I have always advocated good bike set up and being of fundamental importance.

However that is unrelated to the information provided by wattbike polar pedal charts or spinscan which claim to measure effficiency, when indeed they do no such thing.

bahzob wrote:

So I remain sure it is also perfectly sensible to talk about the efficiency of the pedal action in this context. On a trivial level this is obvious. If you try to pedal by pushing down with maximal force when the pedal is vertical you will tire quickly and not go very fast. It is a huge leap of faith imo to assume that because people don't pedal that way they necessarily pedal in the most efficient way possible.

If you try to push down on something that doesn't move, you are doing no work and so there is nothing to measure, efficiency wise.

I completely agree that some people need a lot of help in having a bike better fitted for them, as they will be more comfortable and most likely more effective over a longer period.

It's a huge leap of faith to assume that the Wattbike or spinscan pedal charts are telling us what is most efficient (let alone effective).