Should I Emulate the Pros with My Bike Fit?

With the pro cycling season in full swing, one may be distracted by watching a live stream of a race, a post race highlights reel on YouTube, or lose track of time reading an in-depth piece of race reporting. Often embedded in these pursuits is the unspoken question – “what are they doing that I could be doing to be fitter / faster / stronger / sexier?” The possible answers are many, but might include “should I set my bike up the way they do, and look like they do?” Spoiler alert… probably not!

Let’s draw a distinction between Professional cyclists – who earn a living riding, and Amateur and Recreational cyclists, who do not. Professional cyclists are the One Percent, or more likely the 0.1% of riders. Professional cyclists possess an advantageous mix of genetics, physiology, focus, drive and passion that recreational cyclists – even the best of them – don’t have. Even if we ride the same bikes, we ride those bikes differently.  A better bike fit is not the difference that separates a pro cyclist from an amateur cyclist.

Pro cyclists do have a different bike fit and riding position from amateur cyclists, and there are reasons for that.  As a result, this leads to different equipment and positioning choices that when identified as common themes, get labeled as trends or fads, which in turn are adopted by the overly enthusiastic but much less capable recreational rider, and rarely to their advantage.  Those trends most visible to the discerning viewer or get opined on by the cycling media are:

• Smaller frames
• Longer stems
• No or limited headset spacers under the stem.
• Narrower bars
• Turned in control units
• Shorter cranks
• Forward biased saddle position

For the Pros the intended purpose is to go faster (for longer and at lower energy cost).  But you want to go faster too! Yeah, I get that. But there are differences. Differences relating to both the riders capabilities, and applied physics and biomechanics.

How are Pro Riders Different?

From a fitting perspective, pro riders differ from recreational riders in two fundamental and related ways.

1. Power output is significantly greater.
2. Speed of travel is significantly higher.

Both of these interrelated factors have implications for equipment and fit.

Side note: Higher speed requires higher force production which has a higher cost in calories.  Hence nutrition is such a big deal.  Understanding nutritional needs is important, but unless you are burning through calories like a pro,  you probably should not be trying to consume the same number of calories per hour as they do.

Primary Forces in Cycling

Let’s step away from the details and look at some background fundamentals. There are three primary forces acting on the body of the cyclist whilst riding, and these have different levels of significance for different riding populations:

1. Gravity – via its impact on weight distribution
2. Air –  via the resistance it presents in trying to ride through it faster
3. Pedaling – forces generated directly by the rider, and the reactive forces resulting from this.

Gravity

Gravity manifests itself through its influence on forward/back weight distribution, center of mass location, front and rear wheel traction, bike responsiveness and handling, and muscle recruitment for postural balance and movement propulsion. Gravity is a significant force acting on all riders, but can be countered to a limited degree by the forces of Air and Pedaling.

Air

Air acts as force of resistance to a body in motion working to pass through it. The faster a cyclist wants to ride, the more force they have to generate. The faster one rides, the greater the force required to go even faster. A small increase in speed requires a big increase in force. Hence the science of aerodynamics and its application to cycling: how to go faster with less force than might otherwise be required. This is a big factor for pro cyclists. It’s almost a non-factor for recreational cyclists.

Pedaling

The act of pedaling generates force, and also reactive forces. Pedaling is Newton’s Third Law of Motion in action. For every action there is an equal and opposite reaction. The more you can push down, the more you are being held up. A rider with an FTP of 400W is generating far more force, and resultant force than a rider with an FTP of 200W. Higher pedaling forces can help counter the forces of gravity and air resistance.

Fit Objectives

Now let’s combine these variables and look at the interaction between the cyclist’s capabilities and the forces of influence: gravity, air and pedaling.

Professional Rider

Fit objective: to be as sustainably fast as possible, without unduly compromising comfort and bike function.

As speed increases, the #1 barrier to further increasing speed is air resistance.  Hence the fit priorities in relation to the 3 primary forces are ordered as follows:

1. Air resistance / aerodynamics
2. Pedaling forces
3. Gravity

Air is the #1 force limiting forward progress for a pro rider, all other things being equal. That means aerodynamics is the undisputed priority with pro cyclist fitting.  Gravity is still on the podium but relegated to third place, as the higher speeds and greater wind resistance experienced by pro cyclists, coupled with higher pedaling forces help to offset some of the gravitational effects. Up to a point. There are some compromises in relation to gravity in order to promote aerodynamic advantages. There can be unintended consequences of this, and more than several bike fitters have suggested that this tradeoff has led to an increase in accidents in professional road races due to changes in weight distribution, traction and handling. Some of these are:

• Weight distribution is not centered. Bikes are front heavy. Less traction on the rear wheel, leading to rear wheel slide under power, but also higher propensity for front wheel washout on wet or loose surfaces when cornering.
• Restricted breathing, but not as noticeable due to higher VO2 max scores.
• Over reliance on pedaling forces to counteract gravitation forces.

Amateur / recreational rider

Fit Objective:  to be functional and comfortable on the bike, and ride better as a result.

Riding better could mean riding faster, but it could be for longer, or with less fatigue, or to climb or descend with more confidence and skill.

Hence the prioritization for Force-driven fitting for amateur cyclists is:

1. Gravity – weight distribution
2. Pedaling forces – force generation and pelvic stability (biomechanics)
3. Air resistance (aerodynamics)

Amateur cyclists are not traveling at a high enough speed for a long enough duration for aerodynamic considerations to be paramount, nor are they generating enough force to push back against gravity. Gravity wins.

Equipment Trends

With all of this context let’s take a look again at equipment trends noted earlier, and what their role is:

Smaller frames – than what a similar recreational rider would ride.

• Reason: less weight, lower profile, being able to ride on the hoods as if in the drops – all for less wind resistance

Longer stems – than what a “normal” cyclist would use or find comfortable.

• Reason: The riders still needs enough space to fit on the bike.  If it is lost in frame reach, it is gained in stem length.

No or limited headset spacers under the stem (slammed stem) – compared to the 10 – 40mm an amateur rider might have.

• Reason: not what you might think, which is less weight, or the bike looks faster.  It’s to do with position. Pro riders are rarely seen riding in “the drops” these days. There are a lot of reasons for this, including bar and control unit redesign, but from a fit position perspective, when these cyclists ride on the hoods it’s as if they were already in the drops, without needing to go there (except for sprints). It means the rider is always in the equivalent of the drops. There is no middle ground more relaxed position. Sure they could be on the tops, but how un-pro is that?  So it’s either the drop equivalent (now the hoods) or the super drop  (the actual drops). It’s ALL about aerodynamics.  i.e achieving a smaller frontal surface area.

Narrower bars

• Reason: to bring in the arms and reduce frontal surface area.  Doesn’t matter to these riders if this make the bike less stable, or may inhibit breathing. They have a high enough skill level and VO2 max to get away with it. Mostly.  Aerodynamics for the win!  As this got taken to extremes the UCI stepped in to limit how narrow bars could be.

Turned in control units

• Reason: as above.  This was subsequently limited by the UCI due to safety concerns.

Shorter crank – than the traditional 170 something.

• Reason: to maintain an open hip angle whilst bent lower over the bike with a deeper hip hinge, in order to maintain power generation.  An unintended consequence of a strong focus on aerodynamics is that it can result in more hip flexion which in turn inhibits power production. Hence aero gains can be offset by power losses. Can’t have that. There are a lot of valid reasons to select a crank length other than 172.5mm, but in the progressive teams of the pro peloton it’s about maintaining pedaling force capability and not losing this in the pursuit of aero gains for a net negative loss.

Forward biased saddle position

• Reason: as above. A forward saddle contributes to a more open hip, so this is again about maintaining power production in the face of a lower torso angle and otherwise tighter hip flexion.  Downside: can place the rider out of balance and bias quad dominant force production.

Summary

All these equipment trends are primarily about creating aerodynamic benefits, and when there is risk and evidence those speed gains are compromised by loss of pedaling force, attempts are made to address those.

For most amateur cyclists, following a trend without questioning both the reason for it and the relevance to the individual will likely result in unintended consequences. Ignoring Gravity to worship the Force of Air can result in: forefoot pressure, fatigued quads, saddle discomfort, sore lower back, achy neck, shoulder tension, numb hands, and ultimately less fun and worse performance!

If a renewal of your employment contract depends on the performance results of your cycling, then by all means, go “pro” in your bike fit. But if it doesn’t, then think again. Think about what might be right for you, and recognize that equipment and positional “trends” in the pro peloton are done for reasons that are unlikely to transfer to your own riding.  Each to their own.

Note. No AI was used to write this blog post.