International Bike Fitter Magazine - December 2022 (Issue 5)

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INTERNATIONAL BIKE FITTER DECEMBER 2022 • ISSUE FIVE IBFI MAGAZINE STATIC VS DYNAMIC Comparing fitting styles IS CHASING SYMMETRY ALWAYS THE BEST OPTION? PLUS: IBFI EN ROUTE TO CHARITY STATUS
PROFESSIONAL BIKE FITTING SYSTEMS VELOGIC STUDIO • Accurate, automatic 3D Motion capture • Overlaid onto 2D video • Capture bike measurements • Gorgeous new report • Integration with power sensors and webcams FIND OUT MORECONTACT@VELOGICFIT.COM WWW.VELOGICFIT.COM WHERE ACCURACY MEETS EFFICIENCY CONTACT US FOR A FREE TRIAL
Contents 6 16 20 NEW FACES: MEET THE VOLUNTEERS HELPING THE IBFI TAKE ITS NEXT STEPS WHAT’S THE FUSS ABOUT KOPS? THE PUSH FOR INSOLE PERFECTION 2022 DECEMBER ISSUE 5 President’s letter 2 Static versus Dynamic 8 Striving for symmetry 12 New products 19 IBFI applies for charity status 23 Tried and tested 24 Scientific review 26 Getting the best from social media 24

PRESIDENT’S LETTER

Welcome to the latest issue of the IBFI's magazine, International Bike Fitter . After a difficult few years for many, it feels like fitting seems to be returning to normal in most parts of the world, which is great.

But being busy can sometimes slow down progress on other projects and that's why this issue of our "quarterly" magazine has been delayed — a delay that’s been down to me. This summer has seen several work trips, another international house move and five weeks in Australia training with Steve Hogg — something I’ve wanted to do for almost a decade, and was a

fantastic opportunity to continue my own personal and professional development.

You'll see later in the magazine that we've taken on a couple of great volunteers to help with future issues, which will hopefully prevent my hectic work schedule from delaying future publications. As ever, this magazine is written and put together entirely by volunteers, so if you have ideas for articles you’d like to write, or content you’d like to read, we’d love to hear your ideas.

In this issue you'll be able to read about some of the new faces joining the IBFI ranks to help the organisation continue to develop, as well as a fresh take on some old topics, including KOPS and static anthropometric measurements.

As we announced in the last issue, our transition over to the new common syllabus is taking shape and the e-learning platform to help support the delivery of the online modules from our recognised providers has taken a big step forwards. We should see the first courses promoted on there in the coming weeks.

We also look at symmetry in fitting and whether it should always be the goal of a fit session, and our usual segments looking at new products and interesting tech for fitters.

One of the most exciting announcements though is our recent work to become an official charity. It's something we've considered for a long time and a huge step in cementing our notfor-profit values into the corporate structure of the IBFI.

Charitable status will allow us to accept donations and ensure that your membership fees are spent on promoting bike fitting and the broader industry.

Whilst we’ve always operated as a not-forprofit, it has been out of choice. By becoming a charity this choice becomes a permanent element of the IBFI and removes any doubt from potential members about how we’re run and what membership fees are used for. You can read all about the process on page XX and we look forward to making this long-held dream a reality.

And many of you will be pleased to know that our searchable find-a-fitter map will be relaunched in the coming weeks too. We know that it is a valuable tool for many fitters, and we’ve heard from many of you who have been disappointed that it disappeared.

However, due to the IBFI website being attacked by malicious software at the start of the year we were forced to rebuild the site from the ground up, which turned out to be a bigger job than we first thought.

The original website was several years old and the IBFI has grown rapidly in that time, so the new site will better serve your needs and ensure membership services run more smoothly in the future.

We thank you for your on-going patience and support and look forward to these new website systems helping the IBFI run more smoothly in the future.

Contacts:

Andy Brooke (IBFI President): andy@ibfi-certification.com

Lee Prescott (IBFI Vice President): lee@ibfi-certification.com

Designed and produced by Caroline Stocks Communications • www.carolinestocks.co.uk

International Bike Fitter is published by the International Bike Fitting Institute (IBFI) Unit 9, Hatton Technology Park, Dark Lane, Warwickshire, CV35 8XB, England

NEW FACES

Education Committee

The last issue of the magazine advertised the final three places on the newly-formed Education Committee. With 25 high-quality applicants, it was an incredibly tough decision to reduce the list to just three.

Dr Wendy Holiday (pictured, above) has a degree in Physiotherapy and a PhD in Cycling Biomechanics. You may have seen her present at conferences or advertise hercourses and workshops with Curtis Cramblett. Wendy brings a

wealth of experience in both medical practice and traditional academia.

Winston Tam has delivered bike fitting training for some of the biggest providers in the world. If you’re a fitter in Asia, you’ve probably been trained by Winston or know someone that has.

He’s one of the most active fit educators in the world and responsible for more trained fitters in Asia than any other single individual.

Dr Niels Boon comes to bike fitting with a background in both research and lecturing. With a PhD in physiology and biology, and having lectured in exercise physiology, health sciences and nutrition, he brings a unique perspective on the physiology of bike fit and great experience delivering high-level educational content. Niels now works with Shimano as Team Leader Product Development within bikefitting.com.

Niels helps to write and deliver Shimano’s bike fitting courses.

Website and Digital Team

After the destruction of our old website at the end of last year, we’ve been working hard behind the scenes to bring everything back online. It couldn’t have come at a worse time, with the new education system and common learning management platform (our new online courses website) launching at exactly the same time. The person in charge of the new education system was also the person responsible for the main website, so it quickly became apparent that we needed help. Thankfully, an IT professional from outside the world of bike fitting contacted us to offer just that. With their help, we hope to get not just our websites working smoothly, but all other digital aspects of the IBFI.

Martin Herrmann is a keen cyclist and an experienced Product Manager. He brings a wealth of product management experience and in the few short weeks he’s been involved with the

We’ve recently welcomed a host of volunteers recently to take on key roles within the IBFI. Here, we introduce the new members of the team:

IBFI has already made great towards improving our efficiency and transparency. Jorrit van der Plaats is a bike fitter from the Netherlands who currently lives in Madrid, Spain. Having trained and worked as a fitter in London, UK, Jorrit brings high-level fitting knowledge to our digital team as assistant web developer, well as a keen interest in web design.

Chief Diversity Officer

One of our main objectives with the education committee was to have female representation. To ensure we received applications from female fitters, we contacted all of the IBFI’s female members asking them to apply - there were less than 10, which is less than 5% of the IBFI membership. This isn’t representative of the general population, or of the cycling population, which has seen a boom in female cyclists in recent years.

We need to do better at identifying why female cyclists don’t want to become bike fitters and ensure that we create a supportive and friendly environment for the ones that do choose this career. To that end, we recruited for a new role, whose sole focus will be on promoting underrepresented groups within the IBFI and ensuring equality and diversity within our organisation.

Chloe Murdock has a doctorate in Physical Therapy and has been working in bike fitting for over 10 years. She has experience mentoring both other PTs and bike fitters. She originally applied to join the Education Committee but hr passion for helping female fitters jumped off the page and made it clear she was the right person for this role instead.

Magazine staff

Many hands make light work and that's why we've taken on two additional volunteers to help

with the publication of International Bike Fitter They will help create and manage content, as well as decide on themes for future issues and manage ads and marketing opportunities.

Jon Wild (pictured, above left) is a level 3 bike fitter based in Bristol in the South West of the UK. Jon is an experienced and educated fitter who recently completed his first IronMan triathlon. He has taken over the advertising role and will help with the regular Bike Fit Clinic piece that will return in the next issue.

Jarich Braeckevelt is a bike fitter and data scientist. His research includes studying movement patterns in cycling and he helped to develop training courses and products for major bike fitting brands. He also writes his own blog, which will become a regular feature of future issues of International Bike Fitter .

If you’re reading this and would like to get involved with the IBFI, there are always roles available. We’re also open to suggestions, so if there’s something we’re not doing but you think we should — and you’d like to be the one to help do it — then get in touch: We’re always happy to talk and discuss new ideas.

STATIC VS DYNAMIC

Do static measurements have any value in bike fitting, or are dynamic measurements from motion capture systems and video analysis superior?

Niels Heuvelman from Cyclefit.com looks at the myths around anatomical measurements, and explains why it’s still worth making use of the good things about formulas and body segment lengths.

Ask many bike fitters, and they’ll often say static measurements don’t add much value to their fits. Instead, they’ll tell you that dynamic measurements — generally referring to motion capture systems and video analysis allowing the fitter to measure joint angles — are what’s important.

But while the general idea might be opposed, bike fitting based on formulas and body measurements can still have its place, and it’s worth taking the time to start utilising the good things about them.

Body measurements

All bike fitters I know use some form of body measurements in their daily routine. What body dimensions are measured and how they are used differs between fitters.

In general body dimensions can be used for comparisons between different riders (the more riders you have seen and measured, the easier it gets to see differences between riders), left versus right comparisons (if you measure body dimensions on both sides of the body this will give you an idea about differences) and determining a position or recommendation of certain products, such as insoles or saddles.

If you want to do this, you need more than just the body dimensions – you need a formula or algorithm to go from body dimension to positional recommendation (translating leg length to saddle height). Let’s look at each of these in more detail.

Comparisons between different riders

The Cyclefit system gives us access to a huge number of datasets containing body dimensions.

Since Cyclefit usrs have a specific toolkit to measure the body dimensions, all these are measured the same way following a certain protocol

Figure 2 (below, left) is based on 67,000 data points and shows torso length plotted in relation to the leg length. As you can see from the width of the data cloud, there is a huge variation in torso length at a certain leg length.

If we look at a certain point, for example a leg length of 85cm, we see a variation in torso length from 50 to 70cm. This is a clear sign that measuring one body dimension gives us limited information and that based on one body dimension it is hard to predict other body dimensions accurately.

Figure 3 (below, right) gives a plot of leg length in relation to arm length, and the same conclusion can be drawn here too. Due to the huge variation, it is very hard to create an algorithm that helps us determine arm length based on a certain leg length.

What does this information tell us? Mainly, we can conclude that one-dimensional formulas in bike fitting do not work.

Despite this, they are used more than we realise. For example, most bike brands will give

About Cyclefit

Niels Heuvelman has been in the cycling industry for 30 years. In 2012 he took over CycleFit systems and created his business Cyclefit.com, a company which serves bike fitters across Europe with software, products and education and promotes the use of static and dynamic bike fitting method.

Cyclefit is a bike fitting program based on body dimensions. It was developed around 1990, before data connections were available like they are now, and in the first years the system worked with a Videotex terminal to send the data and receive the report. Later, this changed to a full online system. Over 30 years the Cyclefit system has been used in around 500,000 fits, creating a huge range of data on body dimensions. Some of these data have been used for this article.

Figure 2: Leg length (cm) vs torso length (cm)

Figure 3: Leg length (cm) vs. arm length (cm)

you a recommended frame size based on either body height, or on leg length (inseam height), with inseam length considered to be more accurate.

As shown in the figures, there is a variation of several centimetres in both arm length and torso length in a certain population with the same leg length. Basically, this tells us that the height – length, or in other words, stack – reach relation can vary hugely for different persons with the same leg length (and this is only based on dimensions, it does not take things like flexibility into account).

The collected data also show that there is hardly any correlation between leg length and shoulder width. In other words, it does not make much sense to mount wider handlebars on larger bikes.

Figure 4 (below) shows a plot that relates shoulder width to leg length. Again, looking at the variation the conclusion should be that an offthe-shelf bike most likely needs modification in order to match the rider (which as a bike fitter we

already know).

Can we use algorithms at all?

Based on the data above we could conclude that algorithms in a bike fitting are not very useful, but before doing so we have to realise that all these diagrams are based on a onedimensional approach, meaning we only use one variable to calculate the other. In bike fitting we know that most adjustments depend on multiple parameters. For example, saddle height (knee extension, ankle position) and reach to handlebar (pelvic rotation, shoulder angle, elbow angle).

So, in performing a dynamic bike fit we (consciously or unconsciously) take more parameters into account. When we take more parameters into account when using algorithms, this will improve the quality of the outcome.

The algorithms used in the Cyclefit system, for example, use both leg length as well as foot length (cleat position) to calculate a saddle height. This saddle height is then corrected for different crank lengths and pedal stack height.

Figure 4: Leg length (cm) vs. shoulder width (cm)

This altogether leads to a result which is in line with what using normative ranges for angles would give us (knee flexion 30-40 degree, ankle angle 90-100 degree). Obviously, this is good, but not perfect – exactly as it would be when just using normative ranges and angles.

When we look at the other parts of a bike fit, like saddle setback, reach to the handlebar, and drop to the handlebar, we found similar results, but here as well there are quite a few things to consider such as handlebar reach, handlebar drop, lever reach, saddle length, and so on.

Conclusions

Algorithms can be used in bike fitting, but like with all protocols and techniques the more you are aware of limitations the better they work for you. The main limitation for the use of algorithms is not so much the quality of the algorithm itself,

but the fact that often people expect algorithms to give them the final position.

Algorithms can be great to determine an initial position from here further optimisation can be done. In this sense, they work the same way as normative ranges in angle based bike fits.

The more parameters we have to take into account, the more difficult it is to find the optimum position using algorithms. For example, most of the algorithms currently used do not work well for modern MTB XC racing since the factor of off-road bike handling is not taken into consideration.

When you decide to use algorithms in your bike fitting process, use them the right way; meaning understand what these algorithms do, and what (minor) changes might be needed. Also, remember that algorithms will never be able to beat a well-educated fitter.

NeilsHeuvelman@innova.vecycling.com

FBFAN01072022001FormA5Advertv2PRT.pdf 1 27/08/2022 21:08

STRIVING FOR SYMMETRY

Asymmetry and malalignment is omnipresent amongst the human population, and I’m no exception. The common notion during my physiotherapy studies was that asymmetry and malalignment (compared to the idealised human symmetry) was bad for performance and the root cause of many of the symptoms of pain and dysfunction, which was carried across in my early bike fit education. ‘Fixing’ it was the focus for improving performance, even if there were no presenting issues of pain or discomfort.

With mixed results from the early days of simply following a process of assessing for asymmetry and malalignment, which is easy to find in anyone, I altered my approach from trying to ‘fix’ these ‘issues’ to assessing and treating for pain-free, efficient function.

Professional cyclists are constantly looking for marginal gains, having their biomechanics regularly assessed and re-assessed for maximal

force production and efficiency, whether it's through the use of wedges, foot beds or a strength and conditioning programme (S&C).

Current thinking in bike fitting suggests that pedalling symmetry is the ideal scenario. But the key to any intervention is that it is constantly scrutinised in the longterm, checking for any possible positive or negative effects.

For the non-professional cyclist, this constant re-assessment may not always be possible (location, time, cost), hence an approach of seeking efficient function within the acute time frame setting of the fit studio, and a follow-up where possible.

LEVELS OF ASYMMETRY

There are many levels to human asymmetry and it isn’t always the bad guy it’s made out to be, as we can function perfectly well outside of the idealised symmetry and it won't necessarily lead to an increased injury risk.

UK fitter and physio Scott Cornish explains why chasing symmetry isn’t always the best approach in fitting.

Asymmetry is typically assessed in a coronal, or frontal, plane, comparing left to right in terms of strength, movement, stability, and — as alluded to — the common assumption is that asymmetry is detrimental to athletic performance, although this is not wholly supported in the research (Malony).

Our organs are not positioned symmetrically and humans often display anthropometric asymmetries, such as different sized ears or feet. We develop unilateral dominance, becoming left or right biased.

Skill dominance is acquired through sporting activities and can be task specific. Adaptive asymmetry in limb strength, stability, left-to-right force production and neuromuscular movement patterns arise between the limbs through unilateral sports such as racket sports, ball sports or sweep rowing. How we sit at a desk or bias one leg when standing, injury and physical conditions all contribute to asymmetry.

This doesn’t just affect muscular tissue either, but also the superficial and deep layers of fascia, our global connective tissue. It encases muscle, nerve fibres, blood vessels and is a major sensory and receptor network within our bodies. It is a fibroelastic, dynamic and omnidirectional tissue, important for its role in posture, movement and performance. It’s a key component when considering human asymmetry as it runs from head to toe and in slings around the body. Its properties mean that it is highly affected by injury, surgery, force production and even factors such as stress.

THE PELVIS AND LLDS

A stable and level pelvis is a one of the key elements when looking at asymmetry on the bike and can often be missed when looking uniquely at pelvic angle. It can have an affect on the lower kinetic chain and is one of the first aspects

I assess on the bike. It can easily be positively affected by postural cues to level out the posterior superior iliac spines.

With 36 muscles affecting the pelvis, along with the thoracolumbar fascia and the anterior and posterior fascial slings, any imbalance within these tissues can elicit functional asymmetry in the seated, forward flexed position on the bike, when compared to doing an assessment in prone lying. This is the reason why I would always perform a thorough physical assessment prior to observations on the bike - being mindful of any presenting issues, sporting and medical history, looking for any correlations, or not, with movement on the bike, such as a difference in leg length. Leg length discrepancy (LLD) is a common asymmetry in around 90% of the population, with the average difference not being clinically significant (Knutson), and individuals developing compensatory mechanisms for efficient movement. However, there is no consensus of what constitutes a clinically significant difference, with suggestions that it is as much as >20mm (Michalik) — although this relates more to walking and running. Personally, as a physio, anything >5mm and I would consider an intervention, but only once I had established that there exists an actual difference and not a functional one, which is why both a static and dynamic assessment should be made.

The common assumption is that asymmetry is detrimental to athletic performance, although this isn’t wholly supported in research

We may observe a positive acute mechanical effect, but when an individual has adapted over years to a LLD, it is the long-term effect of function and efficiency that need to be considered, as even a minor height adjustment can trigger an acute negative response in physiological measures of efficiency (MacDermid).

TAKE CARE WHEN SHIMMING FOR LLDS

In prone lying an insignificant difference can be noted (actual), yet as soon as the rider flexes forward on the bicycle, an imbalance in the pelvic associated tissue often produces a functionally significant LLD and an appropriate intervention should be made if this negatively affects the kinetic chain further up, beyond simply adding height under the shoe, as this may lead to long term negative effects. This is an important differentiation to establish, as highlighted by a rider I saw experiencing left hip pain after >1hour riding following a fit session some months prior, where their movement had only been assessed on the bike. A significant LLD was identified and corrected for with two 3mm leg length shims, suggesting a difference of >12mm, as a correction is generally only made for half the difference, due to an already ingrained compensatory mechanisms of the body. A pre-fit, off the bike assessment revealed a non significant difference of around 4mm. Shims were removed over two sessions and an intervention appropriate to the actual nature of the functional difference was made, with

strength and conditioning (S&C) exercises and reducing the handlebar reach.

This resulted in an actual difference of <5mm, where the rider functions well without any associated pain/discomfort, I would be cautious about intervening with LLD shims, simply due to the compensatory mechanisms in place. If I were to see that rider for regular follow ups during the training and racing season, then it would be a consideration where marginal gains are sought, along with some gym based strength work.

WHEN AND HOW TO WEDGE

Similarly, I do not follow a standardised process of measuring foot varus and then fitting x amount of wedges for knee alignment. I actually rarely fit varus wedges, instead assessing what is happening further up the kinetic chain from the foot and giving targeted strength and stability exercises, looking for a long term benefit of both muscle activity and physiological efficiency as opposed to an acute benefit in the fit studio.

It is all based on the individual, of course, and dependent on how compliant that rider might be with an S&C programme. A single wedge may be fitted alongside the S&C with a view to eventually removing the wedge. The 'ideal' alignment may never be achieved and stacking up wedges may be detrimental in the long term, hence improved, long-term function should be the goal.

In the cases of injury or anatomical variations, wedges may of course be required, again with the caveat that S&C is part of the ongoing process of improving function. If we always try to prop up the asymmetry or what is

The 'ideal' alignment may never be achieved… improved, longterm function should be the goal.

considered malalignment, what then happens to the muscular system that has adapted to the asymmetry or malalignment? That system will likely get weaker. Hence an initial or combined approach of an S&C intervention.

With conditions such as scoliosis, again function should be the goal and not simply following a process to align or ‘fix’ asymmetry. Understanding how a rider with this conditions functions off the bike and any surgical interventions they may have had or ongoing treatment and/or symptoms is key to getting them efficient and comfortable on the bike.

INJURIES AND HISTORY

Injury and its lasting effects can often cause asymmetry in movement and force production, a reason why a thorough past medical history should be carried out, to understand what possible limiting physical factors a rider may have. Even wrist and shoulder injuries can affect how a rider holds themselves through the pelvis, through unilateral bracing of the upper limb.

How we approach asymmetries or malalignments that we observe in a session can also have psychological effects on the rider. If you start listing asymmetries that a rider may not be aware of, and how it might affect the body and performance in a negative way, then it could easily negatively affect the rider's mindset, making them worry. It is well known that psychology plays a huge part in performance so care should be taken when describing any findings during a physical evaluation.

Many riders I see don’t know that asymmetry is really quite normal and I will avoid making any

negative connotations especially with more recreational riders, focusing on postural awareness at the pelvis and efficient function.

For the performance-oriented riders who are more body aware, the approach will be more finetuned, but again not having them worry that their left and right knee movements, for example, aren't perfectly matching. I remember once reading about a pro who had an off the bike ankle injury, and expressed concern that the foot movement was no longer ideally aligned as it was prior to the injury, yet he could still perform.

CONCLUSION

We all live with asymmetry and what is considered malalignment. Symmetry is considered the holy grail of performance by some, but how much time do most of us have to chase having a symmetrical body? There is only so much that can be done in the brief fit session, and despite what may be observed mechanically, it's the long term gross efficiency in pedalling that required more research.

Varus wedging and shimming has its place, but it shouldn't be such a common and systematic approach. Positive, long-term functional results can be achieved through an S&C programme or simply by improving pelvic posture. Asymmetry itself doesn't necessarily lead to injury as there could be numerous contributing factors. The body is complex and every rider can react differently to an intervention, but the goal should be improving function and/or reducing pain or discomfort if present. Addressing asymmetry may be part of that, but it shouldn't be the focus to be 'fixed'.

scott@physiobikefit.com

Many riders I see don’t know that asymmetry is really quite normal

What’s the fuss about KOPS?

Knee over pedal spindle has had a lot of bad press over the last few years, but is there still value in the old dog yet? Lee Prescott, fitter and frame builder, thinks so.

KOPS, or Knee Over Pedal Spindle, as I’m sure you are well aware, refers to the practice of using the relationship between the knee (which part is also up for debate, depending on who you refer to) and the pedal axle, in order to determine saddle set back. Or so the myth goes.

But where did this come from? It’s pretty hard to define a clear source, but Fit Kit Systems from the 80-90s used it as part of its protocol, and there is mention of it in the CONI Cycling manual from 1972. It’s likely that it proliferated due to it being a simple measurement that anyone could take, with an inexpensive plumb bob, to get a cyclist pretty close to a decent saddle set back. I know that when I first started building frames in 1986 it was a pretty standard way of deciding on seat angle.

But this is all back when bike fitting was all just a practice of static measurements and conversion formula. The KOPS method became so endemic within the industry it became the de facto process. Dr Andy Pruitt uses it in his protocol

described in his Medical Guide for Cyclists, and Phil Burt advocates its use – but only when taken dynamically – in his book, Bike Fit. But recently, KOPS has become something of a pariah within the industry, with some fitters suggesting that anyone using the method should be avoided.

Keith Bontrager was one of the first highprofile designers to cast aspersions on the use of static KOPS. His famous white paper discusses how the use of a static plumb bob measurement is too heavily influenced by gravity and becomes irrelevant as soon as the bike is on an incline. Part of his reasoning is that it has no biomechanical basis. Now it’s important here to remember that this was written before the advent of power meters or dynamic motion capture. Steve Hogg also wrote about how he was unconvinced by the KOPS method in his blog piece on Seat Set-back from 2011, pointing out that its more important to create a saddle set back that will unweight the torso. Both of these

arguments are well worth a read and are widely available on the internet.

The thing that has struck me in writing this article is how little actual research has been done on proving what the true efficacy of KOPS is. My background is in industrial design and biomechanics/ergonomics, so I have a little insight into a similar field of investigation from another industry.

If you have a spare few moments, take a look into the biomechanics of ascending stairs; you will doubtless find hundreds if not thousands of commercially and academic funded studies. As a fundamental part of everyday life, a lot of time and effort has gone into designing the correct depth and amplitude of stairs.

When you look at studies of muscle utilisation whilst ascending stairs it may look remarkably familiar. Now I know they are not exactly the same, but use of the whole posterior and anterior chains are almost identical as that used when pedalling. So, with all this research where does that industry consider the ideal place of the knee when applying downward pressure? Take a guess!

That’s right. The typical description is of one of the landmarks of the knee to be over the transverse arch of the foot, in the direction of force. It’s that last bit that got me thinking. So, for the last two years, on all fits, we have been observing where the knee is in relationship to the cranks. Not as an academic study but just out of a commercial interest in improving our fit protocol.

We started measuring it on road bike positions by taking the average torque angle of the rider’s effort and then on the simultaneous video capture, graphing where a perpendicular line to the crank in this position would be. In all

instances, once the saddle height was also optimised for the rider’s level of flexibility and torso angle, the knee lined up.

We then started to follow the same process on TT and tri fits as well. Given that the saddle position on a fast bike is normally on the same radius as their road bike, but typically rotated forwards around the BB, we generally see average torque angles around 10 degrees or more further into the pedal stroke. Following the same process on all successful TT fits (the ones where the bike was capable of being adjusted correctly), we saw the same level of correlation.

So, what does that mean? I think we can all agree that using a plumb bob isn’t really relevant any more, but to totally dismiss the relationship between the position of the knee and the position of the foot would be cutting our nose off to spite our face.

Should KOPS be used to define saddle set back? Well, in isolation, of course not. And I think that is the most salient point: Bike fit isn’t a set of simple rules that if you work through you will come to a perfect position.

The biomechanics of the human body is a massively interconnected chain. As we will all have seen in our time fitting, a misalignment at one end can create a problem at the other. Any metric that can help to inform us as to the efficacy of the dynamic position we are working on should be welcomed.

Moving forwards, we will definitely add this metric to our toolbox. It may not be used all the time, but it has become useful alongside some of the other specialised measurements such as measuring wheel weight distribution, pulse oximetry, occlusion detachment etc. that we can use as and when they are needed.

lee@ibfi-certification.com

“Should KOPS be used to define saddle set back? Well, in isolation, of course not.”

International Bike Fitter Magazine takes a look at some of the newest tools and tech from across the global bike fit industry.

Anemoi Aero Extension System

This time trial and triathlon extension system, from Watt Shop, features a modular design with a high level of adjustability. They are manufactured using carbon fibre, SLS 3-D prints and

Time XPRO 12 Pedals

Time pedals are probably the least common clipless system but with the recent acquisition of TIME SPORT by SRAM we can expect this to change.

The XPRO pedals (left) feature a normally open spring mechanism which makes clipping in very easy as you’re not having to overcome the spring tension. The cleats offer a large stable area on the pedal with a stack height of only 13.5 mm, +/ -5° of angular float and 2.5mm of lateral float.

RRP € 306

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Send details to lee@ibfi-certification.com Being featured on this page is not an endorsement by the IBFI

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NEW PRODUCTS

YOU’VE RECENTLY LAUNCHED GEBIOMIZED PUSH INSOLES. WHAT ARE THEY?

PUSH is gebioMized’s semi-custom insole for cycling shoes developed by bike fitters. It is available in three different versions and 15 sizes to make sure every cyclist can find an insole to match their needs.

SOUNDS COOL, BUT WHY SEMI-CUSTOM INSOLES?

Sometimes less can be more. Our experience from thousands of bike fittings shows that not every cyclist necessarily needs completely custom-made insoles for their cycling shoes. But we’ve also learned that the careful selection of a suitable semi-custom insole provides more

stability in the pedalling movement with almost every cyclist. This is why we developed gebioMized PUSH, a semi-custom programme to complement our custom-made products. The main basis is our huge database, with foot pressure data from many cyclists and triathletes — a similar approach to the one we used to design our saddles. PUSH gives bike fitters an edge, especially in their everyday work. After all, there is not only a range of insoles to choose from on site, based on the measurement data, but an effect can be measured by the fitter and felt by the athlete immediately. To provide further support for the selection of the PUSH insole needed by the respective cyclist, we also developed an algorithm-based selector tool.

International Bike Fitter catches up with Daniel Schade from gebioMized to discuss their new insoles and the design approach they used.

THE PUSH FOR INSOLE PERFECTION

Left: The gebioMized team discussing pressure and relief zones of the new insole Bottom right: The different layers being laid out before assembly.

HOW DID YOU DEVELOP THEM?

It took two years to turn the first idea into the final product. Our development team started by evaluating more than 10,000 data sets gathered in the production process of our custom insoles. This database includes measurements from amateur athletes, as well as from winners of major cycling and triathlon races around the world. As a result, we defined different types of stress and identified the respective support elements. Then we created prototypes using CAD, built them in-house and started running extensive tests. We also used our foot pressure measurement system to check how our

prototypes work in real-life conditions, both in the laboratory and outdoors. Based on the results, we revised the models, made new prototypes, and tested them again until we were happy with the objective pressure data and the test riders with how they subjectively felt in their shoes. For the grand development finale, we compared different materials to find the right balance of stability and pressure reduction. This was the birth of the PUSH insole concept; a concept that perfectly complements the knowledge and skill of a bike fitter. After all,

biomechanical know-how is indispensable for choosing the right PUSH model. On a side note, we are proud that the whole development and production process is made in Germany, so we feel pretty robust in terms of supply chains here.

SO WHAT INSOLES ARE AVAILABLE?

The core of PUSH consists of three insole versions offering different support categories, e.g., more stability in the shoe for feet with a flat or high arch. The different layers of every insole provide more comfort by reducing pressure peaks, as well as more stability due to a harder mid layer. Pressure reduction areas provide stress relief for the big toe and metatarsal 1 and 5. As an option, bike fitters may customise the PUSH insole quickly and without special accessories by thermoforming. During development, we were even surprised by the extent the insoles improved the pressure distribution in the shoe. Last but not least, all PUSH insoles are available separately for the left and right foot, so that an individual combination for each customer is possible if required.

For more information visit: https://gebiomized.de/en/products/semicustom-einlagen/

IBFI on the path to charity status

The IBFI has always been a not-for-profit and always will be. But until now it was out of choice

Becoming a charity was always the goal, but in the formative years of the IBFI the extra admin required to run a charity, and the costs involved in the application process, made it incredibly difficult.

With the incredible growth we’ve achieved over the last few years, we’re now in a much stronger position to take that next step. Running as a notfor-profit while being very careful with our spending has allowed us to build up the necessary funds to pay for the application process. And the expansion of our legion of volunteers has spread the workload between more people, allowing us to better absorb the additional admin required of a registered charity.

This month the IBFI officially engaged legal representation to begin the process of becoming a registered charity in the UK. This is a huge step forwards in formalising our objectives and enshrining our not-for-profit ethos into the corporate structure of the organisation. Becoming a charity will allow the IBFI to accept donations and significantly reduce our tax burden, meaning we can spend more of that money on promoting bike fitting and bike fitters.

The process is expected to take around four months and will involve the creation of an entirely new Charitable Incorporated Organisation (CIO).

The current legal entity behind the IBFI, The Bike Fitting Company Ltd, will then be gifted to the CIO, making it a wholly owned subsidiary. With a small restructure, the entire running of the IBFI will then fall under the umbrella of the registered charity.

A little IBFI history for you – the UK (where the IBFI was formed) restricts the use of certain terminology in business names, meaning it was impossible to use the term ‘Institute’ when we first incorporated. The solution was to form a limited company with a different name and then establish the IBFI as a trading name or ‘trading as’ (known in the USA as ‘doing business as’ or DBA). This restriction is eased when applying for charitable status so we’re hoping the new charity will carry the name everyone knows us by – the International Bike Fitting Institute.

So will this new charitable status mean US residents will be able to donate to the IBFI charity and claim the donation back against their tax bill? In all honesty, we’re not sure yet. The process of donating to a UK charity from the US became more complicated in recent years but we’re exploring our options to ensure this is a possibility, including the formation of a US arm of the charitable organisation. We’ll keep you updated as things develop.

Ryden Smart Measurement tool

Imust admit that when I first saw this tool at the Bespoked show last year, my initial thoughts were that it was a gimmick. Upon chatting to Darren Ryden though, it became apparent that a lot of thought had actually gone into the design.

Now Darren is not a bike fitter, and as such did not have experience of measuring many different bikes. After several conversations about the XY coordinate system of measuring a position, Darren was able to feed this new knowledge into the latest design version.

This latest version includes multiple fixtures to connect the tool to the majority of

fitter Lee Prescott

different crank sets. The web app that goes along with the hardware has also seen some major updates to make it more accurate and more useful.

Obviously, the build quality is not the same as something like the Purely Custom XY tool, but it’s not meant to be. With a price tag of under £50, this measurement device is squarely aimed at amateur cyclists and for occasional use.

SIMPLE TO USE

The web app is simple to use and provides a host of information, by utilising the inclinometer of the average smart phone

New bike fit products come to the market all the time, but how do you know which ones are worth buying? UK
shares his thoughts on the Ryden Smart Measurement and setup tool after trying it out in his fit studio.

SIMPLE TO USE: The web app that accompanies the hardware (above) has seen major updates to make the tool (right) more accurate and useful

to determine the angle of the ruler. Then by inputting the measurement taken on the ruler of the saddle or bar height it’s a simple bit of trigonometry used in the code to calculate the X & Y. All of these measurements can then be saved into a profile that stores your set up.

REPLICABLE MEASUREMENTS

The saddle width jaws come as standard at 70mm but can be adjusted to suit any width you are using. The bar gauge now also includes a semi-circular cut out to locate the fixture on the centre bulge on a bar, and the calculation gives you a reading to the centre of the stem clamp.

It's something to say that I have chosen to grab this tool a few times over the XY stick or laser level we normally use and is just as quick and easy to create an accurate measurement. If anything its actually more replicable than both other methods.

All in all, I believe this is a great tool for any fitter to recommend to their clients as a simple way of them replicating a fit onto their bikes or home trainers.

RRP: £49 +P&P https://shop.ryden.bike

Opinions expressed in these reviews are personal and are not endorsements by the IBFI. Products in this article were purchased by the reviewer. If you are a bike fitter and have been using a new product you’d like to review, or if you are a company and you’d like to submit a product for a long-term review by qualified bike fitters, email lee@ibfi-certification.com

How do hip and ankle kinematics predict knee joint load?

Introduction: The primary purpose of bike-fitting is to prevent overuse injuries by adjusting the foot, saddle and handlebar interfaces. The saddle position and the crank arm length influences the lower limb joint kinematics, which can affect knee joint reaction forces. The authors assume that a high knee flexion at bottom dead centre, which is typical of low saddle height, could increase patellofemoral reaction forces. In addition, it has been shown that a posterior saddle position (compared to traditional recommendations) increases tibiofemoral compression forces (Menard et al., 2018). Therefore, the aim of this study was to assess the effect of ankle, knee, and hip kinematics on patellofemoral and tibiofemoral joint reaction forces and identify if sex, horizontal saddle position, or crank arm length also play a role in these reaction forces during submaximal pedalling.

Methods: Forty healthy participants (17 females and 23 males of 28.6 ± 7.2 years) with different

cycling experiences were recruited for this study. First, a fit-bike was set for each participant by positioning saddle height at 109% of inseam length with an effective seat tube angle of 73.7°. The handlebar position was adjusted according to the individual's perception of comfort. All cyclists used the same saddle (Selle Royal, Seta, 143 mm width), crank arm of 172.5 mm and flat pedals with Velcro straps. Then, they used this initial position to perform an incremental cycling protocol (YMCA Sub-Maximal Cycle Ergometer Test) in order to determine the experimental exercise intensity. The pedalling cadence and power output of the last stage (when the participants achieved a heart rate of 70–75% of age-predicted maximum) were used during the following protocol. The experimental protocol consisted to ride in 18 positions during 3 min: three vertical saddle positions (initial and ± 5%), three horizontal saddle positions (initial and ± 10%) and two crank arm lengths (initial, 170 mm and 175 mm), in a random order. The handlebars were adjusted to maintain the same position relative to the saddle. A motion capture system and instrumented pedals measured joint

*Hip and ankle kinematics are the most important predictors of knee joint loading during bicycling, Gatti, A. A., Keir, P. J., Noseworthy, M. D., Beauchamp, M. K., & Maly, M. R. (2021), published in Journal of Science and Medicine in Sport , 24(1), 98-104.

French fitter and researcher Geoffrey Millour looks at a recent paper on knee joint loads as part of the regular literature review feature from the IBFI’s Scientific Sub-Committee.

kinematics and pedal forces, respectively. A musculoskeletal model was made in OpenSim to calculate tibiofemoral shear force, tibiofemoral compression force and patellofemoral force during the last minute of each bout. Mixedeffects models were used to assess the effects of joint kinematics of both lower limbs on the joint reaction forces.

Results: Results show that both flexion and extension of the hip, knee and ankle affect knee joint reaction forces. The resultant patellofemoral joint reaction force was most sensitive to joint kinematics, while the tibiofemoral shear force was least sensitive. All reaction forces were least sensitive to changes in minimum knee flexion (i.e., when the lower limb was extended). The best predictors of tibiofemoral compression force were the minimum hip flexion and maximum ankle dorsiflexion. For the tibiofemoral shear force and patellofemoral joint reaction, minimum hip flexion, maximum ankle dorsiflexion, minimum knee flexion, and the interaction of minimum knee flexion and minimum hip flexion were included in the best predictive model. The inclusion of sex improved fit of all models, but it could be attributed by the difference in power output between males and females (140.4 ± 37.7 W vs. 86.4 ± 30.6 W). The crank arm length and horizontal saddle position were not related to knee joint reaction forces.

Discussion: This study shows the importance of optimising hip, knee and ankle kinematics during flexion and extension in order to minimise knee reaction forces that can be responsible for overuse injuries. Surprisingly, the minimum hip flexion and ankle dorsiflexion were most

important for predicting knee forces than minimum knee flexion, which is commonly used in bike-fitting to adjust saddle height. It appears therefore essential to study the different joint angles both during flexion and extension during bike-fitting to avoid overuse injuries. The authors' conclusion that horizontal saddle position and crank length are not related to knee reaction forces should be taken with caution. Indeed, these settings affect the kinematics, and, as they point out, the inclusion of kinematics in the models made crank arm length and horizontal position variables unimportant. Additionally, the most practical way to limit joint forces by limiting both flexion and extension is to use shorter cranks. It is from this postulate that I studied the use of asymmetrical cranks as an alternative to spacers placed between the shoe and the cleat for cyclists presenting an asymmetry of the lower limbs (Millour et al., 2020). This adaptation, which consists of reducing both extension and flexion of the short lower limb, had shown encouraging results. The influence of sex seems irrelevant, but as the authors point out once again, it is exercise intensity that can significantly affect knee reaction forces. Therefore, the more you pedal at high intensity, the greater the risk of developing pathologies. The use of flat pedals and of an identical saddle for all cyclists, without adaptation time, can be considered as the main limitations of this study. In addition, it would have been interesting to take into account the flexibility of cyclists which can have an impact on the tolerable joint flexion and extension during pedalling. Despite these limitations, this study presents interesting and original results with practical applications for bike-fitting professionals.

The most practical way to limit joint forces by limiting both flexion and extension is to use shorter cranks

There are no hard and fast rules on how often you should post, but only post things you think will interest your followers. Overshare, and you risk people zoning out and ignoring what you put out there.

There’s a great bike fit community online, so get to know them by responding to their stories, commenting on posts, and engaging in discussions. Engaging will also help more people find your account.

Pictures tell a thousand words, but they also spice up your posts and make people more likely to engage with them. Whether it’s a snap of your morning ride, your fit studio, or of a new tool you’re using, keep it well-lit and in focus, and you’ll see the likes roll in.

SHOW YOUR PERSONALITY USE CAPTIONS

Yes, you want to be professional, but that doesn’t mean you should be afraid to show your human side. Injecting some opinions or humour alongside your more serious business posts can help you connect with followers.

10 WAYS

To up your social media game

KEEP VIDEOS SHORT AND SWEET

Videos are great for social media, but to keep people engaged try to keep them short and concise — think three or four stories on Instagram or Facebook.

Social media can be a great tool for promoting you and your business, connecting with other fitters and cyclists, and learning more about bike fitting. Here, we share our top tips for getting the best out of your social media efforts

If you record a video or story, use the auto captions or type out what you said. Most people actually watch videos without any sound, so they could be missing what you say without subtitles. Adding text also makes your videos inclusive.

IGNORE NEGATIVITY

Sadly, trolls are part and parcel of social media, but that doesn’t mean you have to listen to them. Deleting comments and blocking any troublesome followers leaves you free to put your energy into the people who genuinely want to hear from you.

MIX EDUCATION WITH ENTERTAINMENT

People use social media for entertainment as well as education, so try to offer a mix of content, and don’t feel like you always need to have something important or serious to say.

USE HASHTAGS BE PREPARED TO LISTEN

Hashtags are a great tool for helping you reach a wider audience and find people who posts similar content to you. Including relevant hashtags on your posts mean people will be able to find your content more easily — even if they don’t already follow you.

Yes, social media is a great way to share your views and ideas, but it can also be a great learning tool. Rather than just thinking about your next post, take the time to see what else is going on in your network — you never know what you could learn.

KEEP THINGS INTERESTING
INTERACT WITH
USE PHOTOS
FOLLOWERS
APPLICATIONS FOR THE IBFI TRAVEL GRANT ARE OPEN To apply, contact andy@ibfi-certification.com for an application form. More details available on request - GRANT WORTH UP TO £500/€580/$610 - AVAILABLE TO LEVEL 1 AND 2 FITTERS - DEADLINE 31 DECEMBER

GET IN LANE WITH THE IBFI

IBFI members gain global recognition, have access to a host of discounts, can participate in our unique mentoring programme, and apply for the annual travel grant, all for just £10 per month.

Find
out more at IBFI-CERTIFICATION.COM

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