Let's Talk About Bike Fit

At Playtri we’ve always said that bike fit is (or should be) a component of coaching. As a coach I’ve probably fit upwards of 1,000 bikes over the past 7 years – tri bikes, TT bikes, road bikes, gravel bikes, mountain bikes, you name it, I’ve probably fit it at some point.

Along the way, I’ve learned how crucial bike fit is to allowing athletes to achieve their potential, regardless of their level or goals. Want to bike faster? Get your fit checked. Want to bike longer? Get your fit checked. Want to run faster off the bike, prevent injury, enjoy riding more? Get your fit checked.

I always explain the importance of bike fit by describing the rider and the bike as two parts of the same athlete. We talk a lot about muscle imbalances in our sport – if this muscle is too tight, it increases likelihood for injury. If the hips are out of alignment, it causes a decrease in activation and performance. Poor position on the bicycle essentially creates imbalances in the athlete that the rider and bicycle create together by requiring muscles to perform movements and hold positions that aren’t as smooth or efficient as they could be, and may even be damaging to the rider over time.

Following are some of the more frequently asked questions I get regarding bicycle fit, and my responses. Like any area of coaching, bike fit still has a lot of gray area, where rules may or may not apply depending on the rider and the bicycle. At the end of the day, the fit needs to work for YOU – following the rules only matters if you are riding comfortably and efficiently.

 

What makes a “good” fit?

There are a lot of “right” answers to this question, but the simple answer is that a good fit is one that removes any potential barriers to the athlete achieving their goals on the bicycle. A good fit requires both a bicycle that has a geometry (frame size and proportions) complimentary to the athlete’s anatomy and goals, and then (in 99.9% of cases) additional adjustments to the position of various components on the bicycle. Oftentimes athletes will need to replace components on the bicycle (stems and saddles are the most frequently swapped items) to achieve an optimal position.

 

Does it matter who does my fit?

Yes. Best case scenario – find a fitter who comes recommended by a variety of athletes currently riding with no discomfort and/or racing to potential on the bike. Fit philosophies and practices vary widely across fitters, and some are more widely-applicable/successful than others.

 

But I had a Retul/Guru/other computerized fit done – so it doesn’t matter who did it, right?

Wrong. Dynamic fit tools and software are fantastic tools in the right hands. I’ve enjoyed using both the Retul and Guru systems in my time as a fitter. However, they are just that – tools. They do not tell the fitter what adjustments to make – they simply show a greater breadth of information that is collected using a method (dynamic capture versus static measurement) that is truer to life. Ultimately it is the fitter’s decision where in the suggested range of skeletal angles the athlete should be, and how to get them there. A rider could easily have a dynamic fit done twice in the same month by two different fitters and end up with dramatically different results.

 

Should a proper bike fit always feel comfortable?

Almost always yes. There are some exceptions to this rule, particularly for high level road racers and time trialists, and strong short course triathletes – these riders may well need to sacrifice some comfort for aerodynamics and more aggressive handling. However, the rider’s position still needs to be sustainable for the duration of their rides, allow for the power production required by their goals and (in the case of triathletes) not leave them so locked up post-bike that they are unable to access their potential on the run.

 

But what if a comfortable position isn’t as aerodynamic as I’d like?

First, let me start by saying that the fitter’s goal is to help you achieve your goals, so whatever position you end up in should give you the best opportunity to achieve the speed/endurance/run-off-the-bike that you are shooting for. That being said, in my experience this question is usually based on one of the following scenarios. The first scenario is that you may have an unrealistic view of what an aerodynamic fit “should” look like, and what the trade off is between aerodynamics and power production. A more aggressive or aerodynamic fit narrows the rider’s hip angle, making it harder for your posterior chain muscles to activate and produce power. Maybe the increased aerodynamics mean the speed is the same – but you pay for it on the run. Or maybe you just plain can’t produce the power needed to support that position, and you would actually be faster in a slightly less “aero” stance. The second scenario is that you do have a realistic view of where you should be, but your mobility (particularly in the posterior chain – hip/glute/hamstring/back muscles) doesn’t support it. To put it more simply – if you can’t touch your toes, it’s unlikely that the most aerodynamic position on the bike is actually the fastest position for you. Forcing this often leads to low back pain, inefficient power production, and ultimately slower times. To fix this problem – use that foam roller and do your stretching!

 

Will I just get used to saddle discomfort?

I get this question a lot. “MY friends said I’ll just get used to it…” Alright, maybe in some cases, but in general – WRONG. If you can’t keep your full weight on the saddle for the duration of the rides you need to do (i.e. you aren’t constantly shifting or “hovering” around the saddle) then you are not riding at your potential because the bike is not able to support you at your primary contact point, meaning muscles are working on dealing with your discomfort instead of supporting and/or creating power production.

 

Ok so do I need a new saddle?

Not necessarily. Saddle discomfort can be caused both by the saddle and by your position. Oftentimes during a fit we make adjustments to saddle position and other parts of the bike that cause the rider to suddenly have a comfortable position on the saddle. However, when the fit is properly adjusted and the rider is still having uncomfortable/unsustainable pressure, it’s time to look for a new saddle. If possible come to a place like Playtri where you can test different saddle options during your fit before making a decision.

 

Does it matter what I wear for my fit?

YES. Your apparel can 100% affect the quality of your fit. Always wear skintight kit (cycling or tri), no baggy material anywhere. Short sleeves and shorts (versus tights) are preferable because they allow the fitter to better see what the muscles/bones are doing at the knee and elbow joints. Bring the cycling shoes and pedals you plan to use with the bike as well – a fit without your cycling shoes is dramatically different than a fit with them.

 

I had a fit done – why didn’t it fix my (fill-in-the-blank) pain?

There are two possible scenarios here. The first scenario is that the fit still isn’t where it needs to be. You may need a follow up with your fitter so they can reassess and adjust based on your feedback (we offer free follow ups at Playtri for this very scenario), or you may need a different fitter. Use your best judgment here, and keep in mind that it is not uncommon to still encounter challenges after an initial fit – things can happen after 3+ hours of riding on the road that just can’t be predicted in the fit studio! The second scenario is that the fit is about as good as it can get, and you need to look at the volume and intensity you are doing on the bike, as well as your recovery practices (again – foam rolling and stretching matters!) Bike fitters aren’t magicians, and we can only fix issues related to position – not those caused by overuse.

 

I keep cramping on the bike – will a fit fix this?

Maybe. Cramping is a neurological failure that can be caused by overuse (which could be due to poor position) or depleted hydration/nutrients. Lack of proper hydration (water + electrolytes) is a common cause of cramping on the bike, so no guarantees a fit will fix this issue, but it could help.

 

Can my fit actually help me run faster off the bike?

Believe it or not, yes. Studies have shown that triathletes whose hips are in a more forward position on top of the bottom bracket (versus the further back position common in road bikes) can run over 10% faster off the bike. Why? The jury is still out on the specifics, but check out the Garside study “Effects of Bicycle Frame Ergonomics on Triathlon 10K Running Performance” from 2000 if you’re interested. On this note, if a fitter references your triathlon fit as a TT or time trial fit – it’s not. UCI has specific rules governing saddle position for time trial riding that dictate the saddle being a certain distance back from the bottom bracket, and these rules do not apply to triathlon. It could be a slip of the tongue, but remind him or her that you are doing triathlon, not time trial racing. If they tell you it is the same, consider finding a different fitter.

I got my bike fitted when I bought it 5 years ago – so I’m good, right?

Wrong. Bike fits should be updated as frequently as once a year because your body is constantly changing, your goals likely change every so often, and it’s not uncommon for parts on the bike to slip or wear out as well. In essence, the fit that was perfect for you last year may not be perfect today. If you start to notice increasing pain or tightness that you didn’t notice before and isn’t associated with specific changes in training, that would be another clue that it’s time to have your fit looked at.

 

Do you have questions about bike fit?

Email headcoach@playtri.com for answers! Coach Morgan Hoffman has been fitting bicycles at Playtri for 7 years and is one of the lead fitters at the Playtri Dallas Store. She also runs the Playtri Coaching Education Programs and Team Playtri Elite. Learn more about Coach Morgan at www.playtri.com/morgan.