INTERNATIONAL
BIKE FITTER I B F I
M A G A Z I N E
MEASURING UP FOR SUCCESS Our 10-page special on what to measure and how
IS LOWER ALWAYS BETTER? Busting the myths around aerodynamics
Photo by Dmitrii Vaccinium on Unsplash
APRIL 2021 ISSUE THREE
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Contents
02 PRESIDENT’S LETTER
05
MEASURING UP FOR
25 IS LOWER ALWAYS FASTER?
SUCCESS - 10-page special report Fit first - the importance of measuring
6
New products
20
Straight to the point - a metrologist’s view of
Tried and tested
21
measurement
8
Last but not least - the importance of shoe
The how and why of X and Y
12
molds
23
Cafe Stop - James Thomas
15
News
22
IBFI is six - a look back at what we’ve achieved, and where next
Scientific review: Do face masks affect 16
exercise capacity?
27
2021 APRIL ISSUE 3
PRESIDENT’S LETTER I know the pandemic completely distorted our sense of time this last year, but you’re not imagining it — it has been longer than three
fantastic content written by fitters and experts from across the world. This issue steps things up further with even
months since our last issue. Our great editorial
more great articles, but to keep our progress
team had a lot on at the back end of 2020, so we
going we’re asking for your help. We’re looking
took the decision to push back issue 3. The extra
for volunteers to help us put together the next
time has given us the chance to create a
issue, so if you’re interested in writing an article,
fantastic issue of Bike Fit International though, so
fancy being featured in our ‘meet the fitter’ page,
we hope you’ll forgive us!
or you want to learn more about putting together
When we started this magazine, which is
a magazine, then get in touch. Regardless of how
entirely written and produced by volunteers, we
much time you have to spare, or whether you
imagined it would include a handful of articles
have any writing experience, there are lots of
that would be read by a couple of hundred fitters.
ways you can help.
But the reaction from readers has far exceeded our expectations: Our first two issues have been read by over 2000 people, and we’ve published
GETTING BACK TO NORMAL Since our last issue, Covid has remained a huge part of our lives, but there’s finally some
light at the end of the tunnel. The vaccine roll out
A return to racing will mean a return to training for
is picking up speed in many countries, and
many of those triathletes and fitters should be a key
hopefully infection rates will decline enough that
part of that process. In preparation for the rush once
we’ll be able to return to something approaching
our clients are back training to full capacity, we’ve
a normal life by the middle of the year. Many
pulled together a special section on measuring bikes.
education courses had to be cancelled or
Across a bumper 10 pages, we feature articles
postponed in 2020, so please consider attending
looking at the different ways to measure a rider for a
a course when they open up again. A large
bike, and the measurements we need to take so that
number of these businesses have been the
we can accurately transfer that position between
backbone of our industry for a long time, and the
bikes. We also have the second part of a great
pandemic hit some of them hard; if you can
feature on wind tunnels and aero testing (if you
support them by using their products and
missed part one, you can find it in issue 2), along with
services, then please do.
all our usual regular features.
It’s been great to see the innovative
On a personal note, I’ve recently started mountain
responses to the many restrictions imposed
biking and I’ve been able to enjoy Arizona’s fantastic
around the world by Covid, with fitters offering
winter and spring riding in the desert. As the
remote services and a huge number of webinars
temperatures have picked up recently, the local
and workshops popping up online. Whilst a lot of
rattlesnakes have started to come out of hibernation
aspects of fitting can be taught remotely, there’s
— something I never had to face back home in
no substitute for a hands-on approach, and
England! Thankfully they don’t tend to be aggressive
hopefully we’ll be able to return to that soon.
unless provoked, but as some of the most poisonous snakes in the world, I’m definitely giving my exotic
READY TO RACE With any luck, we’ll also be able to see a lot
trail buddies a wide berth. I hope you enjoy this issue as much as we have
more racing this year, and the grand tours will
enjoyed putting it together, and that 2021 is a positive
return to being the spectacles they always were
shift from 2020. As always, if you have any feedback
with fans lining the roadside. The lack of racing
or ideas for future issues, we’d love to hear from you.
has definitely impacted demand for Tri bikes in
Stay healthy!
certain markets, and whilst the industry as a whole might still be massively up on previous
Andy
years, the Tri bike market has certainly stumbled.
andy@ibfi-cer-fica-on.com
International Bike Fitter is published by the International Bike Fitting Institute (IBFI) Unit 9, Hatton Technology Park, Dark Lane, Warwickshire, CV35 8XB, England 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
T
here are multiple ways to measure a bike, with little consensus on what constitutes best practice. Getting it right can be the difference between success and discomfort, so taking the time to measure things accurately is incredibly important. Over the next nine pages, our special report looks at all elements of bike measuring — as well as measuring people for new bikes — from what to measure, through to how to measure it. Written by experts from across the industry, our series of articles will get you thinking about your own practise, and whether you can make any improvements.
Photo by Munbaik Cycling Clothing on Unsplash
MEASURING UP FOR SUCCESS
FIT FIRST:
THE IMPORTANCE OF MEASUREMENT Purely Custom’s Zeb Miller runs us through the best way to use measuring tools and software to identify the best fitting bike
T
hankfully, more and more cyclists are realising the importance of fit — and some are even realising the importance
of getting a fit before buying a bike. The days of a customer walking into your fit studio with a new bike and saying “it’s a different size to my last bike, but it was a great deal,” are waning; the fit first mentality has taken over and, thankfully, looks like it’s here to stay. When you fit your client before they buy their next bike, the process needs to be a little different and two key questions are thrown up. Do you do the fit on their existing bike or on a size cycle? And how do you identify what new bike would work best once you’ve completed the fit? Each of those questions will massively impact the final result for your client, so let’s walk you through what we’d suggest.
Size Cycle or existing bike? It depends on the client. If they like their current position, start there, because it might not be far off and you’ll get an extra level of detail from seeing how they ride currently and what compensations they make than you would from starting with a blank slate. If you see pretty quickly that the position is a long way off, you can easily switch to a size cycle, but that information alone might help explain why the correct position you’ve given them at the end of their fit may feel strange to them. If their existing position is fairly close, then by
by Photo
all means complete the fit on their existing bike. That way, if they plan on keeping the bike, they
Immo
have a good position on two of their bikes and
plash n Uns ann o
Wegm
they can be riding in your suggested position while waiting for delivery of their new bike.
The point that you switch over
The search results list bikes along
to a size cycle is when you know
with their suggested stem length,
you can’t achieve the position you
angle and headset spacer stack, but
want on their existing bike and
each one can be adjusted by you.
you’ve gathered all the data you can
So, if you want to use a handlebar with
from their current riding habits.
a little vertical rise on it to claw back
You don’t want the restrictions of
some front end height, you can adjust the
the current bike to impact the decisionmaking process for the next one. For example, if you’ve flipped the stem and just can’t get high enough at the front
position to get you where you need to be. Check the reach on your client’s handlebar too. If you’re struggling to find a bike with the
end, don’t guess, put them on a size cycle
right handlebar X number, then a bar with a
and find out how much higher they need to
different reach might just help you get there.
go so that you don’t suggest an expensive mistake.
Remember, your rider will be spending most of their time in the hoods so the handlebar XY figure assumes you’re using a bar with the same
How to identify the next bike Start off with handlebar and saddle XY measurements. The XY tool is great for a quick and accurate measure of the handlebar and saddle position relative to the bottom bracket. With these key numbers and our Pure Position software, you can search a huge database of
reach. If your client’s next bike will have a different reach, adjust for the difference in your handlebar XY figure. For example, if the current bar reach is 85mm, the new bar reach will be 75mm. Increase the handlebar X measurement by the difference (85-75=10mm).
current bikes and find the best option for your client. After nearly a decade of development, Pure
Conclusion There are lots of options when fitting
Position was released in 2013, providing shops
someone for a new bike but the right tool for the
with their very own in-store geometry expert. The
job will always make your life a lot easier, and
software can calculate the position of either a
hopefully make the end result more accurate too.
handlebar or a saddle to within a tenth of a
There’s no better feeling than helping a client
millimetre. Even the most finicky of riders
find a bike they love, but they’ll definitely love it a
wouldn’t be able to feel that difference.
lot more if you use a fit-first approach and make sure whatever they buy will be comfortable and
#ProTopTip Normally, our software will find a bike within a millimetre but sometimes the closest you can find will be several millimetres away, so what do you do next?
suitable for their intended purpose.
Zeb_miller@purelycustom.com
Photo by Brian Wangenheim on Unsplash
Straight to the point A background in metrology — the study of measurement — means Dave Archer, President of UK-based Arch Design Works and designer of the Velo Angle system, knows more than most about what points are of interest when measuring a bike.
W
ithin Cycling, point definition is not
stack heights would allow simple translation from
trivial, as there isn’t universal
the BB.
agreement as to what locations should serve as references. Using the BB-saddle-handlebar/arm pad
The saddle reference is the most problematic corner of the triangle, as the appropriate spot is both difficult to reliably locate and difficult to
triangle as an example, the bottom bracket is the
agree upon where it’s located. Early conventions
only location that is universally defined.
like the saddle tip or in-line with the seat tube
Unfortunately, as it is not a point of rider contact,
were driven more by convenience than function.
it is the least functional of the three. This
More recent suggestions, such as a distance
illustrates the common situation where history,
from the tip as a proportion of overall saddle
convenience or other considerations influence
length, are improvements, but not directly tied to
convention.
anatomical features that determine position.
The bottom bracket is the logical origin for
Latest suggestions of referencing the saddle
dimensions convenient for frame selection.
at a particular width, (most published suggestions
However, the majority of riders seeking
are between 70 and 80 mm) appear a logical
professional fits will apply the results to existing
attempt at setting a more effective convention for
bikes. The ideal reference would be the surface
rider position, particularly if saddle changes are
of the shoe insole. While this may seem
contemplated. Figure 1 (next page) depicts a
impractical, a compilation of pedal/cleat and shoe
design for establishing and documenting a
is a common source of error. Positive location
reference point anywhere on the saddle surface.
can be defined as basing the measurement
As riders are very sensitive to slight changes in saddle tilt, accurate documentation is important. While the typical ‘Panini Press’ across
precisely on the point intended and being able to do that consistently. Figure 2 (below) provides a good illustration
saddle length of is fine for a given saddle, the
of these concepts with terms that are commonly
option of isolating the rider’s contact as shown in
used, but often not fully understood. Note that
figure 1 makes dialling in saddle changes much
the terms precision and repeatability can be used
easier.
interchangeably. Inaccurate but repeatable measurements are
Locating points of interest during
usually the result of improper tool calibration or
measurement
test setup. For example, if a seatpost diameter
Locating is not redundant with defining, as the lack of positive location of the reference point
was measured with a set of digital callipers that
wasn’t zeroed properly, or if measurements were made on a bike that wasn’t plumb and level.
The source of compromised accuracy and repeatability is usually some combination of the measurement system and user technique. Readings taken with tape measures or levels are highly technique dependent. The combination of cross-line lasers and fixed scales provide a stable measurement system, but location of the origin and reference features are still visual and not positively located. The validation studies of multiple measurements of a known standard that are common in industry are rare in activities like bike fitting. Because the rider that gets a professional fit is likely conscious of small variations, assessing your current technique will be time well spent. A
The potential for error is reduced as the
common source of measurement error in fitting is
distance between the point of interest and the
parallax — the difference in apparent location
reference is reduced. Camera-based systems can
when a feature is viewed from different lines of
also have significant parallax errors depending
sight. An example is shown in Figure 3a (below).
on sensor design and location. Figure 3b (above) shows an example where the point of interest is in contact with the scale, as was also the case in figure 1. Digital readings, such as the angle measurement in figure 3b, are inherently free from parallax.
Apply a measurement system to capture the relative location of reference points Fixed systems (cameras, cross level lasers, jigs) whether optical or mechanical rely on the bike being aligned with the system. To get an idea of how much minor misalignment impacts measurement accuracy, a CAD study was performed on the author’s primary road bike (56 frame) assuming a 1 degree levelling error. As the saddle is not located at the midpoint of the wheelbase, error varies depending on which
wheel is high. In this case, each degree of
foreign to bike fitters as this is the primary
levelling error results in an average measurement
parameter for establishing rider position. The X-Y
error of 13.3 mm in X and 4.8 mm in Y.
approach became a bike measurement standard
Fits performed in trainers often have this level
largely because it was consistent with readily
of error because establishing a true level plane is
available gravity-based hand tools like levels and
not simple. The angle-based system discussed
plumb bobs. However, it seems logical that the
can eliminate the need to level the bike by auto-
format used to describe the rider’s position on
zeroing the level plane to the bike’s orientation at
the bike should be consistent with that used to
the points of wheel contact or the QR nuts.
define where they contact the bike.
This direct point-to-point measurement based
For example, the author’s 106 mm handlebar
on length and angle (polar coordinates) has
drop is of limited usefulness without knowing the
significant time and accuracy advantages over
associated length. On the other hand, expressing
any approach that requires separate
drop by angle (in this case -8.1°) is much more
measurement of X and Y.
universal. Figure 4 (below, left) illustrates how
While defining bike setup using angles is uncommon, this approach should not seem
expressing the relative location of bike contact points by length and angle can provide a more intuitive means of correlating bike and rider data in addition to providing the benefits of direct point-to-point measurement.
Note from the author: My goal was to present a cycling metrologist’s view of how bike setup might be more effectively captured and replicated and to provide some food for thought. The product images are of a tool and app we developed to enhance accuracy and flexibility at an affordable price. darcher@archwerx.com
The why and how of
XY Photo by Eduard Delputte on Unsplash
Measuring positions with XY co-ordinates is the gold-standard of measuring contact points in bike fit. UK fitter and IBFI Vice President Lee Prescott explains the concept.
I
’m sure even the most inexperienced fitters
drawing board (yes, I know, showing my age). I
amongst us will have come across a situation
was always taught to create engineering
where a client has come in to your fit studio
drawings to the old BS308 standard. This
complaining that they just can’t seem to get their
standard took a very dim view on chain
position right, even though they’ve transferred
dimensioning due to its lack of accuracy and the
their dimensions from their old bike, which was
fact that discrepancies in your measurements
comfortable, onto their new one.
accumulate as you work through the chain.
When you then delve into this, it becomes
Many years ago, when we started to formalise
apparent that they’ve made the normal mistake of
our fitting protocol at the studio, it didn’t even
measuring up the seat tube to get saddle height
occur to me to measure a rider’s position in any
and then adjusted the bars to some relationship
way other than XY coordinates. I simply
with the saddle. This method of measuring the
measured the riders position in the same way
bike is effectively chain dimensioning (see box).
that I would annotate it on a drawing. It was only
My background is in industrial design and I spent
several years later that I discovered that tools
my formative years working at a parallelogram
such as the Purely Custom XY device existed. But isn’t this just over complicating the process of
Chain Dimensioning is when dimensions are drawn from one feature to a second feature, then a third feature is located relative to the second feature.
measuring a bike you may ask?
FUNDAMENTAL PRINCIPLE The fundamental principle that underpins the process of getting one bike to fit like another, is
that it is the rider’s position that needs to be
bar in the right place. This tends to get the
measured and not the bike specifically. Really, all
athlete into a pretty decent position before fine-
we trying to do is locate two points in space from
tuning.
a datum.
By using this method, one of the key benefits is
The obvious datum point is
that not only is your position always the
the centre of the bottom
same, but your weight distribution across
bracket, although I would say this as this is usually the datum you use when designing a frame, too. It
“
is the perfect starting point, because without any work the first contact point is already defined as
By using this method, one of the key benefits is that not only is your position always the same, but your weight distribution across the bike will tend to be pretty similar.”
the bike will tend to be pretty similar, due to the fact that your weight distribution in relation to the bottom bracket will always be identical, keeping your centre of gravity in its ideal location. Obviously, the caveat here is that the bike frame needs to be the right size. If a rider is trying to get comfortable on a frame that
having the coordinates
is obviously too long or too short for them,
0,0.
then the weight distribution is going to be
Then by simply defining
incorrect.
the relationship between
SIMPLE DIMENSIONS
the other two contact points by means of a
The simple dimensions diagram (image below)
vertical and horizontal dimension, you have a
that we supply our clients following a fit denotes
rider’s position effectively captured. The specific
the four XY co-ordinates along with bar width,
points we use are the centre of the stem clamp
crank length and saddle width. Yes, we add some
and the top of the saddle, at the 70mm width
other detail into their report such as bar shape
point, as we have found this is a pretty good
and drop, saddle type and so on, but the basics
approximation of where the middle of the Pubic Rami will sit, i.e. we are locating where the pelvis is, not where the saddle is.
MIRRORING OUR FIT APPROACH What I love about this method is that it mirrors the way I generally approach a fit to begin with. I normally concentrate on getting a rider’s power centre set up by adjusting the relationship of the saddle to the bottom bracket, and then adjust the upper body to suit the intended goal of the fit by placing the
can create your own X and Y axis by simply placing the back wheel of your bike (or even a Watt Bike) up against the wall. And then by taking reference measurements from the wall and the floor to the bottom bracket, you can infer the other two contact points.
FUTURE STANDARDS I’d like to think that some of the bigger manufacturers would start to think about this method a little more when they are describing their bikes. Canyon seem to be leading the way are all there on one simple diagram. We do the
on this with their Stack+ and Reach+ system for
same for TT bikes, just using two points in space
bar position. It is also a pretty simple task to
for the bars (back of arm pad and tip of
define the saddle position range in identical
extension), which are defined in exactly the same
terms. I actually did this for the last production
way.
frames I designed for our own bicycle range.
One of the questions we get asked a lot about
Just imagine looking at geometry charts that
the dimensions we supply to our clients is ‘how
instead of being filled with largely irrelevant
do we replicate this on to a different bike at home
dimensions such as head tube length, you only
without any of your fancy tools?’. In fact, we’ve
have to check two position ranges, one for the
been asked it so often we created a YouTube
bars and one for the saddle.
video to explain the process of transferring these dimensions. The simple answer is all you need is
Lee Prescott, IBFI Vice President and owner of
an upright wall and a tape measure (above). You
Velo Atelier, Warwickshire, UK
lee@ibfi-certification.com
Star of YouTube’s Bike fit Tuesdays, James Thomas, of Richmond Cycles, London, braves the hot seat in our latest IBFI fitter profile.
How untidy is your fit studio? Ask my staff…
Describe an average working day for you I
Very! But only in the places customers can't see.
wake up, ride my bike to my shop, have a shower/
Image is key.
breakfast, do some email, first fit, lunch over
Who’s the most famous person you’ve ever met
email, second fit, another hour of email, ride
in your job? Over the years I've fitted Richard
home, ditch bike collapse on sofa and do the
Branson, Gordon Ramsey and most recently Tao
same again the next day. Bike fitting, it's rock and
Geoghegan-Hart just before his Giro victory. You
roll.
choose who you think is most famous!
How did you get to where you are today?
Tell us something not many people know about
Working bloody hard for people who don't get it.
you I used to teach scuba diving on the Great
I'm lucky enough to be my own boss now and am
Barrier Reef.
able to do things exactly the way I want do them
If you had to get a job outside of cycling, what
— fit first, buy later!
would it be? Beer taster, nuff said.
What’s your favourite event in the cycling
What’s the best thing about what you do? - How
calendar? - Paris-Roubaix! Cobbles, dirt0p and
rewarding it is. A rider comes to me with pain,
beer!
sometimes so debilitating that it impacts their daily
What’s the weirdest thing a fit customer has
life and being able to help them achieve their goals
ever said to you? Can we have a picture?
is hugely rewarding.
What advice would you give to someone just starting out in bike fit? Go on as many courses as you can to learn as many different points of
Espresso time Twitter or Facebook? Instagram! [James posts as @bikefitJames and has over 40,000 followers] How do you take your coffee? Strong and black What pedals do you ride? Road, SPD-SL, MTB SPD What saddle do you use? Several, as I have several bikes! Favourite road saddle at the moment is the Selle Italia SLR Boost S3 Favourite place to cycle? Spain
view.
https://favpng.com/
IBFI cafe stop: James Thomas
This year marks the sixth year since the first conversations that started the IBFI. Over that time, we’ve achieved a lot, and while there’s still plenty to do, that doesn’t mean we can’t take a little time to celebrate what we’ve done so far.
WE ARE Steering Committee and Certification The IBFI steering committee contains some of the world’s best fitters, fit educators, and technology
other. It used to be a very insular profession with fitters often being afraid to talk to their competitors. But the reality is that improving the whole industry increases demand for fitting services, after all, a rising tide lifts all boats. One of the ways we can help
manufacturers. Without a
develop ourselves and the
group of that level, the
industry as a whole, is by
IBFI never would have
speaking to other great fitters
got off the ground.
across the world and sharing
Although they had
our experiences. Our
different approaches to
Facebook group allows our
fitting, they…
members to do just that.
MEMBER BENEFITS
Mentoring programme We’re really proud of our mentoring
Education can be expensive, and it
programme, which pairs early-career fitters with experienced mentors to help guide
becomes even more expensive when you factor
their development. The mentoring programme
in travel, accommodation and loss of income for
includes an assessment process that helps
independent fitters for the duration of the course.
fitters gain more credits and work their way up
By creating a £500 grant, we hope to reduce
the IBFI ladder. These mentoring relationships
those cost a little and make international
have led to friendships and support networks
education opportunities a little more accessible.
that extend well beyond the mentoring
Facebook group
programme.
The IBFI has helped to break down barriers and encourage fitters to talk more openly to each
Conference
Photo by Natasha on Unsplash
Annual Travel Grant
In 2019, we organised our very first
relevant scientific publications. It’s a great
conference. IBFI Asia was held in Thailand with
project that helps fitters across the world stay
delegates from across South East Asia and as far
abreast of developments in research, even if they
afield as the UK and US. It was a great success
don’t have access to scientific journals.
and before Covid struck we were in discussions over running it again in 2020. Once it’s safe to
WHAT’S NEXT?
travel again, we’ve no doubt that more IBFI conferences will be on the cards.
Our goal is, and always has been, to create a respected and recognised bike fit profession.
Democratic Presidency During 2019 we also rewrote our constitution to shift towards a democratic model, where our President, Vice President and Steering Committee will be democratically elected from our membership base from 2024.
There are still a few missing pieces to
“
that puzzle but we’re working hard to
Our goal is, and always has been, to create a respected and recognised bike fit profession.”
reach that objective.
Insurance Conversations are on-going to create global liability insurance products specifically for bike fitter. Insurers struggle to understand what we do and misjudge the risks involved, meaning the policies available for fitters either
Quarterly magazine 2020 saw the launch of this magazine — a small project that
don’t cover everything they need or are unnecessarily expensive. We’re hoping to change that, and have already taken steps in
quickly took off and turned into what
that direction. It’s looking like it’ll be a longer
you’re reading today. As a single point
journey than we’d hoped, but it’s a top priority for
of focus for our industry to share
the next few years and something we feel is
developments and best practice, International
important for our industry as it continues towards
Bike Fitter is the first industry publication for bike
becoming a respected profession.
fitting. Common education standards Scientific sub-committee We also re-launched our Scientific Sub-
We’re aware that our certification system has some weaknesses but it’s a transparent and fair
Committee in 2020 under the stewardship of US-
system that was a great start. Our next steps are
based IBFI level 4 fitter Chris Balser. Chris has
towards agreeing a common syllabus for bike
done a great job creating a team whose goal is to
fitting, one based on the European Qualifications
help disseminate scientific research. The team
Framework that gives us a vocational pathway
meet to discuss future research projects, identify
towards one day achieving a Diploma in Applied
areas of cycling biomechanics that require further
Cycling Biomechanics. This system would
investigation and create layman’s reviews of
provide fitters will have a clear pathway from
starting their careers to becoming a well-
noticed that our Constitution allows for regional
rounded, educated professional. Split across four
committees, once membership levels are
levels, they’d also be able to stop their learning
sufficient. We hope to reach a point where North
at any point, with no pressure or need to continue
America, Europe and South East Asia/Australia
all the way to level 4 if that didn’t match with their
will become the first three regional (or
career goals.
continental) committees. They’ll be able to run
The qualification could one day count towards
their own conferences, decide how to spend
university credit, but in the first instance we’re
some of their region’s membership fees and work
just keen keep improving the industry and raise
to promote bike fitting and bike fit education
education levels across the globe. We’ve been
across their region.
consulting with key education partners already
We’re also experimenting with non-English
with some great feedback and are keen to reach
language websites with a first new site launching
out to more people looking to offer bike fit
in France later this summer. We need to do a
training. If you’re a bike fit educator and would
better job of breaking down language barriers
like to know more, please get in touch with IBFI
and talking about the IBFI to fitters in their native
president Andy Brooke (andy@ibfi-
language; hopefully our French language website
certification.com).
will be the first step towards further international sites or translated areas of the main IBFI
Website redevelopment and integration
website.
We’re going to redevelop our website this year to help better integrate and automate our membership application process and payment
A Bright Future From where we started six years ago to
system. As a volunteer-led organisation, the more
where we are today is a great achievement and
we can automate, the more time they have
one that wouldn’t have happened without the
available to work on other projects, achieve our
dedicated volunteers that help run the IBFI. If we
goals and improve the service we offer to
can achieve our goals, then bike fitting really will
members.
take a step out of the shadows, carried out in the back corners of bike shops, and into a modern,
BikeFitBites.com To further support the great work our Scientific Sub-Committee are doing, we’re
structured profession with globally recognised standards and a professional body worthy of the name.
creating a standalone website to make it easier to search through their review articles. As the number grows, you’ll be able to search for reviews based on their topic and much more easily take a deep dive into the relevant research.
Further International Development The eagle-eyed amongst you will have
Want to get more involved with the IBFI? No matter where you are in the world, we’re always looking for volunteers. Email Andy Brooke to find out more.
NEW PRODUCTS
AeroLab Universal Angled Armrest Wedges With many recent TT bikes with integrated front ends it has become difficult to get the riders arms
International Bike Fitter shares some of the newest tools and tech from across the global bike fit industry
into a decent angle, which has lead to the proliferation of aftermarket wedges and adapters for various bikes. This set of wedges are available in UCI legal 15 degree and 20 degree inclinations. The real benefit
AirPop Active+ Halo Smart Sports Mask
is they will fit the majority of arm rest fixtures, as they can mount to any bar and arm
More than your average face mask, this product
rest that uses M5
filters the air to reduce bacteria and particle
screws spaced
inhalation, while also measuring breath rate.
between 15mm
Filters last for 40 hours of exercise, offering up to
and 35mm. This
99.3% particle filtration (PFE) and 99.9%
makes it really easy
bacterial filtration (BFE) — good statistics to
to stock them in a fit
have as we all try to work safely during the
studio with limited stock
pandemic.
requirements.
The smart mask is available in one size, but
The wedges are made using a deposition form of
comes with adjustable ear
3D printing and then reinforced using stainless
loops so you can
steel. This keeps the manufacturing costs low as
ensure the perfect fit.
well as the weight, although they should only be used under the arm rest and not within a bar stack
RRP £149.99.
as they are not designed to cope with those sorts
Replacement
of forces.
filters cost £29.99
Note: These are not to be used such that they are
www.airpophealth.com
incorporated into your stack. They are for use directly under your arm rests only. RRP £35
www.aerolabuk.com
Got a product you’d like featured? Send details to lee@ibfi-certification.com Being featured on this page is not an endorsement by the IBFI
New bike fit products come to the market all the time, but how do you know which ones are worth the investment? Lee Prescott shares his thoughts on a product he’s been using in his own bike fit studio.
Purely Custom X/Y Tool
the machined in gauges ensure that even if the paint wear out, the tool is still just as accurate.
When I was first deciding how to measure rider
The spirit levels are a little inaccurate if you want
positions, I was trying to work out the quickest and
to get into really fine detail work, but with the
most accurate way to collect the dimensions I
simple addition of a digital inclinometer you can
wanted. I settled on using a hanging rule in
get within 1-2mm. I would say this tool qualifies
conjunction with a laser cross level on the BB
as one of those must-haves, which is evident by
centre. This works fine in the studio where I have
the long back order list Purely Custom seem to
wheel jacks and my custom saddle gauge, but
have for them.
when I was travelling it was not so great.
RRP $295
Then I discovered Purley Custom’s X/Y tool. I
www.purelycustomfit.com/product/xy-tool
bought mine from the European distributor, Gebiomized, and it’s been in constant use ever since. The machined aluminium construction has proven to be tough and reliable even in the rain in a field in Belgium. For such a simple concept it’s amazing how many uses we have put this to. It’s great for comparing bikes, like-for-like, in the studio and provides client with a really selfevident visual of how a bike might work with their position in real life rather than on a screen. Being able to simply set it to a stack and reach and then use it to explain the differences between different bikes they may have is invaluable. The quality of construction is excellent and Lee’s X/Y tool has been in constant use since buying it.
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
Last but not least Shoe molds — or lasts — are critical to creating a wellfitting show. Christian van Asten of Lake shoes explains.
M
aking the best fitting cycling shoes
a narrow foot. With each design decision, the
requires a combination of three distinct
last potentially fits fewer and fewer feet.
variables: materials, pattern design and
Most shoe brands use various materials and
last shape. If you change any one of those
have multiple designs that are changed
variables, you change the way a shoe fits’
seasonally but are still built on the same last
However, the last shape provides the most
shape, which helps them to keep their costs.
constraints to achieving a universal fit.
Similar to creating molds for carbon frames,
WHAT IS A LAST?
there can be significant cost in the making of
A last is the foot-shaped mold that a shoe is
the last, so making multiple models of shoe
made around. Too pointed in the toe box and it
from the same mold can help keep costs down.
doesn’t fit squarer feet; too narrow and it won’t
There is a train of thought that models at all
work for a wider foot; too wide and it won’t support
price points should fit consistently, which is often used as an argument for using the same
COMFORT PLUS Our new ‘comfort plus’ last, available in the new the CX201 shoe, was designed specifically to help riders with less angled toe alignment squarer/flatter toe box shape). The foot shapes that are targeted are commonly known as Roman, German, Celtic, Asian and African. By opening the toe box more to reduce pressure on the lateral toes, riders can potentially wear a shorter length shoe which will affect the last across multiple models. But changing just the materials and design patterns without changing the last shape means the fit will be very similar, but in more and more cases the adjustment needed is much more radical. This means that brands who use a single last often provide a broadly similar fit across all their models, and consumers would be better served by switching brands if a shoe doesn’t fit, rather than switching models.
MANAGING VARIATION Obviously, feet vary hugely — not just in size but also in shape and volume — so a brand that wants to offer a wide variety of fit solutions has no alternative but to use multiple different last shapes. There is no such thing as one perfect last that will work for all cyclists. One distinct last shape, if you’re lucky, will fit comfortably about 30% of the riding population, and as rider demographics shift and expand, that percentage is getting smaller. The need for multiple/distinct last shapes is more important now than ever. Even with five distinct last shapes (comfort, winter, sport, competition and race lasts) and up to four different width variations (standard, wide, extra wide and women’s) Lake’s research has found that there is still a need for at least one more different shape.
cleat location. Many riders with these foot shapes will size up their cycling shoe to get the room needed for their toes and that will put the cleat location typically too far forward. One other key point to consider with last shapes is arch profile. Riders with lower arches or more mid foot volume can feel discomfort with high arch cycling shoes. With a carbon sole, once the arch is too high, there is no way to make internal adjustments needed to gain complete comfort. Lasts with a flatter sole profile allow the rider and fitter more options to make internal adjustments via insoles or shims.
chris&an@lakecycling.com
Cyclologic unveils first global education partners U
S cycling analysts Cyclologic have
to start working with each member of the
announced the first bike fitters to join their
partnership to ensure quality bike fit education is
innovative global education partnership.
available across the world.”
Fitters operating across 11 countries have signed
The first five partners, who will receive one-on-
up to become members of the Cyclologic
one training from one of Cyclologic’s US-based
Education Partner Network (CEPN), an initiative
team of experts, include Stockholm-based fitter
which aims to deliver gold standard education
Iain Fidlay, who will be covering Denmark,
content to cycling analysts across the globe.
Finland, Iceland and Norway, Tim Plunkett from
As well as being trained to deliver Cyclologic bike
Guelph in Canada, and Swiss-based Chloe
fit education courses, the partners will be given
Murdock, a US doctor of physical therapy who set
support in running their own education centre,
up her bike fit studio in Zurich in 2019. Jason
while providing input into course content to help
Adames will be covering the Caribbean and parts
ensure the courses remain at the cutting edge of
of Central and South America, while Jean Luc de
scientific understanding.
Meyer will be working with fitters in Belgium and
Paraic McGlynn, Cylcologic CEO, said the CEPN
the Netherlands.
members would help to expand the reach of
Cyclologic are looking for additional partners in
Cyclologic and ensure a new generation of
other key markets and will be running their first
expertly-trained fitters worldwide.
train-the-trainer events later in the year.
“The pandemic may have delayed many
For more information email Paraic McGlynn
education opportunities across the world, but it’s great to see so many companies planning for a post-COVID future,” he said. “We’re really proud to be building such a highcalibre network of educators, and we’re excited
Got news you’d like to share in International Bike Fitter? Email andy@ibfi-certification.com For advertisement enquiries email lee@ibficertification.com
Photo by Jean Gerber on Unsplash
IS LOWER ALWAYS FASTER? In the second article in this two-part series, UK physiotherapist Bianca Broadbent and physiologist Barney Wainwright – who are both bike fitters – discuss the need to individualise aerodynamic interventions to make athletes faster. Read the first part in Issue 2.
I
t can be difficult to gain insight into the process
cockpit 40mm resulted in a considerably more
of aerodynamic optimisation thanks to the large
aerodynamic position for Cyclist A (37W lower
number of biomechanical and aerodynamic
power requirement to achieve the air speed),
factors at play — and their complex interaction.
which was more sustainable and was found to
These complexities mean that, sometimes, the optimal position involves making positional changes that may seem counterintuitive and may
offer an increased ability to produce power. It should be noted that while these are examples where a relative increase in the cockpit
be contrary to some athletes or practitioners' beliefs. However, these results and outcomes also demonstrate the importance of using an individualised evidence-based approach, where assumptions are minimised.
TRUNK ANGLE AND POWER The assumption that a lower torso position is a fast solution reflects current bike positioning culture. However, this is a very reductionist approach and fails to consider the individual rider and their unique body shape and functional abilities. As can be seen in figures 1 (right) and 2 (next page), raising the Figure 1. Front on views of baseline posi5on (le7) and final posi5on (right) for Cyclist A.
position in the wind tunnel if the cyclist cannot maintain nor ride in the race environment in that position. Despite this, there is a trend to adopt a narrow pad position as in many cases this reduces the frontal area. There are many criticisms to this approach, namely that when the rider is producing power their head may be more likely to “pop up”, as it may to also improve vision, but it does not consider the flow of air around the rider. Underwood et al. (2013) suggested that there’s high variability in aerodynamic drag with pad width and this is a very individual adjustment. If the cyclist does not have the anatomy or function to permit such a forced Figure 2. Baseline run v set up 7, Cyclist A (side view). Note that despite the higher cockpit, this position created less aerodynamic drag, and was more comfortable and powerful than the forced baseline.
position, then a narrow arm pad position will
height reduced aerodynamic drag, this is not a solution that is applicable in all cases, and for some anthropometric qualities a lower cockpit position can be more advantageous due to the changes in air flow that occur. This was certainly evident with Cyclist B — see later in this article — where widening the arm pads created space for the shoulder girdle to retract and as such allow the torso to adopt a lower overall position. The key element here, is that there will always be an interactive effect when a position is changed, as widening the cockpit would not have facilitated a lower torso angle had the saddle height not been lowered first.
PAD WIDTH Position sustainability is incredibly important for longer distance events, but also to permit large volumes of training in-position for short events. There is little point in adopting the fastest
Figure 3: Baseline (top) and final (bottom) position. Note the lower torso angle because of widening the arm pads. It is important to iterate that the cyclist is able to see ahead in this position although it looks like they are looking downwards.
create more issues than it will resolve (Conti-
sustainable position than the baseline and
Wyneken, 1999).
created a direction on which to focus in his
Figure 3 (below) shows the baseline position for Cyclist B. In this position there is a great deal
preparations for upcoming races. This process has created specific knowledge
of strain through the shoulder and cervical
from which further refinements resulting from
musculature, with little opportunity for the head to
experience of long training rides and races can
be tucked. Widening the pads provided good
be put in place.
proprioceptive and mechanical stability to the
EQUIPMENT
lateral forearm and allowed the head position to drop substantially. Raising the hands of the cyclist so the
The purpose of the examples in this article has been to present information on positioning. However, we have also included some data to
forearm is inclined is another method that is
show the effects of equipment choices that
commonly utilised to optimise the aero position.
occurred in these sessions.
This “closing of the gap” more commonly
While some general trends exist, there is
facilitates a more relaxed shoulder girdle, and as
considerable variability in the impact of
such can allow the rider to pull down into a lower
equipment that is determined by the
position figure 4, below). The aerodynamic
environmental conditions experienced (air speed,
outcome of this intervention is highly variable,
direction) and the role its particular shape has on
with very high hand positions often obscuring
the whole system. Equipment can rarely be
view of the road, and sometimes increasing
assessed in isolation.
cervical extension. It was agreed with Cyclist B that these interventions created a far more comfortable and
Helmets are a good example of this, where the size and shape of a helmet on its own cannot determine how it interacts with the rest of the body. With cyclist A, we mentioned in our previous article that the large size helmet was not aerodynamically effective. However, the smaller size of the same helmet model increased the aerodynamic resistance by 7 Watts, or approximately 1.3 seconds over in her event. With cyclist B, the top tube mounted nutrition bag/box, which can often increase aerodynamic resistance, in this case reduced it by the equivalent of 6 Watts, or approximately 66 seconds over an Ironman race distance.
Figure 4: Frontal view of the baseline (left, with narrower elbows) v final position (right, with wider elbow position).
CONCLUSION As with any commercial service that aims to
occur. This 'functional window' allows us to ensure good adaptability, and crucially, the ability
be as cost-effective as possible, there will be
to hold a sustainable position whilst producing
some limitations on time utilisation, and
power.
prioritisation of the key areas for optimisation is crucial. The examples and case studies we’ve
Key priorities are to tailor the session to the athlete’s goals and ensure you consider the biomechanical and physiological demands of a
presented across our two articles are not an
position — the position with the lowest
example of a robust research study, but simply
aerodynamic drag is not always the fastest
serve to highlight the potential gains that can be
overall.
achieved with individuals for whom aerodynamics and power are highly important determinants of race outcome. There are many approaches that
Equipment will have an interactive effect with the position, and it is better to optimise this last. The outcome that can be achieved is
each professional can take when looking to
determined by the resources, approach, and
optimise an individual’s position, which will be
experience available. If there is a good evidence
shaped by their background, experience,
base and a sound process, then a near optimum
resources, and team.
solution will be determined.
Some may prefer to establish a matrix of possibilities, i.e. what are the fastest
Bianca @thecyclephysio Barney @bgwainright
aerodynamic positions and how can they be facilitated biomechanically. Others, as we do, prefer to establish a robust biomechanical position on which aerodynamic refinement might
Don’t forget you can read the first article in this series in issue 2 of Bike Fitter International. Click here to read it.
In the first of a series of scientific reviews, courtesy of the IBFI’s scientific subcommittee, Glasgow-based fitter Nuno Gama summarises research looking at the cardiopulmonary impact of wearing surgical and N95 masks during exercise.
T
he use of face masks to limit or stop
FFP2/N95 mask. The study involved 12 male
indirect pathogenic transmission of
volunteers (age 38.1; SD = 6.2 years) with a BMI
the coronavirus disease 2019
of 24.5 (highest normal; SD of 2kg/m2), recruited
(COVID-19) is perhaps one of the most
from the medical staff at the Leipzig University
controversial topics in the sports performance
Hospital. Cardiac output, stroke volume, heart
scene of current times. With most governments
rate, VO2max and spirometry data (see digram,
adopting compulsory mask usage policies, there
below) were collected continuously at rest, during
is debate emerging whether respiratory capacity
the task and during recovery.
is diminished in healthy, athletic or populations with decreased lung function.
Fikenzer and colleagues (2020) looked at the
Participants completed three ramp tests to exhaustion (with 48h between tests, each one corresponding to a mask condition, randomised
differences in cardiopulmonary exercise capacity
prior to testing) but were not blinded to the type of
between three mask conditions: no
mask. The stepwise protocol consisted of a 50W
mask, disposable surgical mask and disposable
increments with the duration of 3 minutes and an
Tidal volume - amount of air breathed during normal respiration Inspiratory reserve volume - amount of air inhaled above tidal volume during a deep breath Expiratory reserve volume - amount of air exhaled below tidal volume during forceful breath out Residual volume - amount of air left in the lungs after max exhalation Vital capacity - the most amount of air in a max exhalation after a max inhalation Inspiratory capacity - total volume that can be inspired after the end of a normal breath cycle at rest Functional residual capacity - volume of air left in the lungs at the end of a passive respiration at rest
Photo by engin akyurt on Unsplash
Cycling through Covid: Do face masks affect exercise capacity?
initial step of 50W until voluntary exhaustion. To
mask did not differ from the “no mask” condition.
understand the spirometry results, the diagram
These results seem to suggest that the use of the
provides information on the parameters
more robust FFP2/N95 mask will decrease
measured on a respiratory test.
oxygen availability and as such, respiration becomes slower but more strenuous. It would be
RESULTS At rest, results show that tidal volume did not differ across conditions, but that breathing
interesting to measure thorax expansion to understand if forced vital capacity correlates well with the “breathing harder” hypothesis.
frequency was reduced for the FFP2/N95 mask alone (from ~15 bpm to ~13 bpm). This could mean a higher pressure force is needed to
ANALYSIS Contrary to the authors’ conclusions, I did not
overcome the higher airflow resistance offered by
see clear and sustained evidence from this study
the FFP2/N95 mask. This in turn reduced the
that a surgical mask is any different (in
frequency of respiration to a slower, but more
cardiopulmonary and metabolic measures) than
effective (since all haemodynamic parameters
not wearing a mask, during exercise.
were also maintained)
If we consider that at rest
breathing. The forced
there were significant
vital capacity was
reductions in function with a
significantly reduced by
surgical mask and that these
the masks (~8%
dissipate during exercise,
reduction for surgical
then we can assume that any
mask and ~12 for FFP2/
air resistance introduced by
N95 mask). This is
the surgical mask is
significant because it
overcome by breathing
suggests both masks
harder. The same is not true
limit the amount of air passing through the mask at max inspiration and exhalation. At maximal load, the results show reductions
for the FFP2/N95 mask. One limitation of this study is that the sample of participants can be considered untrained
in tidal volume (from ~3 L with no mask, to ~2.7 L
cyclists (2h of physical activity per week, not
with the FFP2/N95 mask), breathing frequency
specified to be cycling). A plethora of research
(41 bpm no mask, 37 bpm FFP2/N95 mask) and
confirms that untrained cyclist show a greater
ventilation (131 L/min no mask to 99L/min FFP2/
acute metabolic response to exercise than trained
N95 mask). These reductions were for the FFP/
cyclists, so it would be interesting to test if the
N95 mask alone and no differences were found
respiratory and metabolic changes seen with
between “no mask” and “surgical mask” in all
mask usage by untrained riders are present in
physiological and cardiopulmonary parameters.
trained cyclists (or even intermediate riders or
Furthermore, maximal power and maximal
commuters). For example, if a cyclist rides to
oxygen uptake were reduced only by the use of
work every day, will they overcome the
the FFP2/N95 mask, and results for the surgical
physiological deficits introduced by the mask, as
we see in hypoxia training? It would be also
impact on cardiopulmonary capacity” (Fikenzer et
valuable to determine the minimum amount of
al., 2020), but, it is possible that the increased
cycling (per week) needed to overcome the
resistance to airflow introduced by the masks
detrimental effects of mask usage. Furthermore,
could be offset by the increase in air pressure as
we know novice riders experience greater muscle
the cyclist travels through air (we know that the
coactivation when compared to trained cyclists
faster we ride, the more air pressure we build up
(e.g. Chapman, Vicenzino, Blanch, and Hodges,
in front of us). Could the positive air pressure that
2008), despite similar timings in EMG
builds up in front of the rider be enough to offset
peaks[MOU2] . This coactivation results in longer
the air flow resistance introduced by the mask?
periods of muscle activation with a direct
This study introduces an important concept in the
metabolic consequence. For this reason in future
“new normal” methodology of training and cycling
research it would be important to randomly
against air resistance is an important research
include individuals with different training levels to
question that needs addressing.
understand if the results presented in this study are an effect of the mask usage, or the level of training of the participants. Lastly, the increase in airway resistance introduced by the masks was identified by the
Nuno Gama, PhD, is the founder of ORBIS LaB, a laboratory for advanced biomechanics and sports performance, based in Glasgow, UK.
authors as the main reason for the “negative
International Bike Fitter NEEDS YOU Want to help us create the next issue of International Bike Fitter magazine? We’re looking for volunteers to write and put together content for future issues, helping us continue to grow the publication and build on the great success we’ve achieved so far. A good standard of written English is desirable but not essential. Tasks may include: • Writing • Identifying authors to submit articles • Editing • Sourcing images • Coming up with ideas for features • To find out more about how you can get involved, email Andy on Andy@ibfi-certification.com
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