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Bike Fit for Performance, Aerodynamics and Injury Management

This article takes a comprehensive look at the importance and impact of a proper bike fit, from the perspective of a chiropractor/coach/pro triathlete (Dr. Cindy Lewis-Caballero) and a coach/F.I.S.T. certified bike fitter/triathlete (Alan Caballero).

Questions for Cindy

  1. What are the most common cycling related injuries you see in the triathletes you treat and train?

ITB syndrome, Achilles Tendinosis, Piriformis Syndrome and Low Back pain

  1. What distinguishes an injury as specific to the bike, vs swimming or running?

It’s often hard to tell!  We tend to blame many injuries on the run that may not actually have been caused by running initially.  We typically run after cycling and cycling is so repetitive that often tissues are getting tighter and tighter and tighter and then on the run the pain or discomfort presents itself.  The swim is most often the culprit for shoulder injuries and this is easy to see after a physical exam and perhaps a swim stroke assessment.  It is important to note, though, that shoulder injuries can also be related to cycling and bike fit.  If you have a shoulder injury that has been treated and seems to never want to go away, perhaps get your bike fit looked at as well!

  1. How does a proper bike fit play a part in either the creation or treatment of those injuries?

Cycling is very, very repetitive. If you ride at 90rpm that means every minute each foot goes around the pedal stroke 90 times.  That’s 5400 times per hour.  And many of us ride much longer than an hour!  You can see how a small error in bike fit can lead to an injury over time due to the repetitive nature of the sport.

  1. How do strength and flexibility fit into proper bike fit?
    This is more for Al to answer – but my answer will be that the more flexible you are through the hips and back, the deeper and more aggressive a position you will be able to get into comfortably on your bike.  And, therefore the more “free speed” you can attain from the bike fit.
  2. As a pro triathlete, how has bike fit made a difference for your training and performance?

My first professional bike fit was done when I was experiencing chronic piriformis issues (achey pain in my glute).  The fitter adjusted my bike and perhaps more importantly took a look at my feet, my shoes and my cleats and placed shims in the shoe to adjust the position of my feet in order to alter the pressure on the bottom of my foot when I pedal, the alignment of my knee and the function of my hip throughout the pedal stroke.  It made my pain go away very quickly!  A proper bike fit also influences your power output and speed both in a positive way.  A proper fit positions you to use the muscles in your hips more effectively as you pedal, leading to more power.  If you’re looking for performance (which I am!) a proper fit will also put you into a position that will optimize aerodynamics and maximize the speed that comes out of every watt.

  1. From a coaching perspective, are there different requirements for bike fit based on an athlete’s training/race distance or physical bias to strength vs speed?
    Long distance = more comfort. Fit is important so the athlete is able to remain in aero position for more of the bike ride.
  2. What indicators should an athlete pay attention to on the bike that suggests an injury is in the making, and is their position on the bike the first consideration to look at?
    Any pain that doesn’t feel like muscle pain simply from doing a workout!  Any pressure or hot spots on the feet, pain in the joints (feet, ankles, knees, hips) pain that doesn’t go away in a day or two.  These are all indications that the person needs to be checked out by their chiropractor or physical therapist or their bike fitter, or a combination of all three.  If they go to their chiropractor and physical therapist and despite proper treatment and rehab the injury seems to persist when and after they cycle, bike fit should definitely be looked at.
  3. As a coach and pro triathlete, how would you rank the importance of aerodynamics, comfort and access to nutrition for yourself and for your athletes? Is it possible to optimize all three on a bike set up?
    A balance of comfort and aerodynamics is important – and as the race distance gets longer, comfort becomes more important… to a point.  We want our athletes to be in aero position for as much of the race as possible, and if they don’t’ have a good bike fit, they won’t be comfortable in aero.  Basically you want to get as much aerodynamic benefit as possible out of a fit that is comfortable enough that you can ride in aero position for a long time.  As far as nutrition is concerned (which is an entire article in itself!), it’s definitely important to be able to access nutrition, and there are many ways to carry nutrition to make it work.
  4. Some athletes use an alternate bike (road bike) on their trainer and a tri bike for the summer race season. Does this practice make any difference to the athlete’s abilities or performance?

Ideally an athlete trains on the bike that they will race on.  The more specific you can get in training – with equipment as well as workouts – the more you will get out of every workout.


Questions for Al

  1. What are the most important things for an athlete to know before starting a bike fit? It is important to know that a fit has to be comfortable and maintainable in order to optimize on power and aerodynamics.  If you aren’t comfortable, you won’t be able to hold your position or power.  It’s true that most of the aero positions in triathlon and in road racing being utilized by elite and professional athletes are attainable, but work is required to increase flexibility and strength to support that position so it’s ultimately comfortable to that rider.  I think it’s important to enter a fit with an open mind and be able to accept if the bike they have truly won’t fit them.  It’s also important to know that your fit is a snapshot of now and your fit does change as you change in flexibility, strength, ailments etc.
  2. What are the most important things to know about an athlete before starting a bike fit?  The most important thing to know about the athlete are the goals they have and what they typically like to race, past and present injuries, and the hardware they currently are using that they either will continue to use on their bike or that will be transferred to the new one, such as pedals, power meters, cranks, and handlebars/aero bars.
  3. Is it possible to optimize aerodynamics, comfort and access to nutrition – or does the athlete need to prioritize which is most important? Does the answer depend on the athlete’s goals and capabilities? It is important to optimize comfort first, this will put you in the best position to put power down as well as hold an aerodynamic position.  Small tweaks like head positioning can be made from there to help improve aerodynamics in that comfortable position.  As for access to nutrition, there are plenty of aftermarket and O.E.M. (Original Equipment Manufacture) products out there now that are catering to aerodynamic shapes to prevent less of a penalty in terms of drag.  Between-the-arms bottles, rear cages, bladder systems, and top tube bento boxes are stock on some superbikes or available as aftermarket additions, and have helped improve the drag-producing atrocities like gels taped on top tubes and round bottles mounted on frames.  The athlete must practice retrieving nutrition from these storage areas, as they can be quite tricky while riding.
  4. How important are the athlete’s strength and flexibility for a bike fit? Strength is important in holding the position fitted.  If your core is weak, there will be excess movement being made by the body instead of transferring that energy to the pedals.  A good fit will leave the athlete balanced, without feeling too much weight on one part of the body than necessary.  Flexibility is really important when trying to achieve comfort in a more aggressive aerodynamic position.
  5. As the athlete trains throughout the season, is there a reason to expect their position on the bike will change?  If the athlete works on their flexibility, as well as have become accustomed to the aero position, tweaks to the position could be made.  If there is an injury sustained during the season, a fit can be adjusted to accommodate it, but it’s highly recommended to see a sports therapist such as a chiropractor or physiotherapist who has experience dealing with athletes to treat the problem first.
  6. Does the race distance affect how the bike should be fit? If so, and assuming the athlete uses one bike, how do you handle the athlete who races both short and longer distances? An aerodynamic position is only as good as long as it can be maintained and being really low is not always more aerodynamic.  One would think two positions would be required for short and long races but both positions would still need to be comfortable.  Keep in mind, unless aerodynamic testing has been performed, comparing both positions in a consistent environment, it will be uncertain if one position is more aerodynamic than another.  A position that can’t be held resulting in moving around and even rising out of the aerobars and onto the base/pursuit bars will slow you down.  Having a comfortable position that you can hold as well as efficiently apply power will be faster.  Also, being too horizontal will work against the body in keeping stomach contents down, so for longer races where fueling plays a factor, this must be taken into consideration.
  7. Starting with the right bike and the right size frame seems to be critical for getting bike fit right. Since trying to retrofit a bad purchase usually ends in a compromise, what guidance can you offer an athlete who is thinking of a new purchase and wants to make sure they start with a good foundation? Starting with the right dynamic fit is critical for selecting the correct sized bike for the rider, especially on these triathlon superbikes with integrated cockpits, which are becoming more common place.  Trying to make a bike shorter or longer horizontally will not only affect the steering and upper weight distribution, but it may be limited to future adaptations as your fit evolves with your mobility/flexibility/injuries.  Stem length, which is the primary adapter to accommodate the fit parameters, could place undue stress on the fork steerer if set too high or too long.  If too low, it may put the drops on a road bike or pursuits on a tri bike at too low of a position.  If too short, it will affect steering response.  A dynamic fit will produce the fit coordinates needed to take the guess work out of choosing a bike and limiting it only to the bikes that can actually fit you optimally and allow for future changes in most directions.
  8. For athletes on a budget, what bike adaptations would you prioritize for the bike to optimize their bike for racing? Getting a bike fit that places you in an aero position that is comfortable and maintainable for the length of race or rides will provide the most benefit.  A bike fit that’s not comfortable will result in the rider moving around and even going up onto the base/pursuit bars to alleviate some discomfort.  An aero helmet will provide a great watt per dollar return for a rider and is one of the cheaper “modifications” to start with.  Clip-in shoes along with cleats can maximize the power applied to the pedals and cleats that have been fitted to compensate for the natural varus/valgus of the foot can help apply pressure evenly to the pedals and alleviate discomfort.  Wearing tight fitting tri top and shorts will help smooth the air around the body.  Avoid putting water bottles on the frame by utilizing hydration between the arms (bottle cage mount or specifically designed hydration system) and/or rear bottle cages mounted behind the seat.  Be sure to practice reaching for these first on the trainer before trying it on the road.
  9. For athletes who are competitive, or can afford to max out their ride, what would you consider to be the ‘whistles and bells’ that will optimize their performance?  An integrated front end that smooths out airflow along the frame of the bike, usually found on triathlon or TT super bikes, deep carbon wheels, oversized pulleys, ceramic bearings, waxed chain are examples of “the bells and whistles” improvements to be made on a bike.
  10. When travelling with a bike, how can an athlete safeguard against messing up all the work done in a fit when the adjustments are so specific? One way of preserving the fit dimensions is to mark the seat post and handlebars with electrical tape to where two separate components meet.  Another way is to take pictures of these meeting points.  Ultimately it’s best done with a tape measure and a level for most accurate results if you want to do it by yourself, otherwise arrange for a bike mechanic to re-assemble your bike.
  11. How much does bike maintenance and tuning affect performance? Bike maintenance and tuning can affect performance of the mechanical systems of the bike quite a lot when they are all added up together.  Some of the simplest gains can be made by having a clean and lubed drive train that is properly tuned.  Up to 10 watts can be saved with a clean drive train and using the right lubricant can net you 4-6 watts additional from your standard chain lube.  A derailleur that is not tuned correctly or cable/cable housing that has been stretched or compromised could result in having to continually fiddle with it throughout a race or ride. It can also cause the chain to jump up or down to the next cog which will affect your momentum of applying power, thus slowing you down while you hunt for the sweet spot in the correct cog.


CLPerformance Training helps athletes achieve fitness, performance and lifestyle goals through participation and competition in endurance sport. Coach Cindy Lewis-Caballero is a doctor of chiropractic, certified coach, personal trainer, and professional triathlete. Coach Al Caballero is a F.I.S.T. certified bike fitter, coach, and triathlete.