The importance of posture

In his IBFI mentoring assessment, Utah-based Australian fitter John Higgins of BikeFitr and Fit Kit Systems, explains why good posture matters when it comes to comfort and sustainability.

Regardless of whether we are sitting, standing, walking, running, sleeping, or cycling, the influence of gravity is ever present. Posture is how we align and hold our body to counter the relentless force of gravity. The central focus of posture is the alignment of the pelvis and spine, which together provide the foundation for the movement of the upper and lower extremities.

From a bike fit perspective, it is worth considering how a cyclist might best align their pelvis and spinal column to function at an optimal level on the bicycle. Posture is not the same as position. Position takes into account the arrangement and movement of the upper and lower limbs in relation to the spine, and to each other. A cyclist’s position is commonly defined by joint angle measures, and indirectly documented by bike set up measures.

Although the use of motion analysis can provide comprehensive data and useful insights into a cyclist’s position and function, point-to-point measurements oversimplify the postural presentation of the person. A cyclist may exhibit the same position as defined by joint angles, but present with a notably different posture – with implications for energy efficiency, comfort, and performance.

Benefits of optimal posture

A cyclist’s posture on a bicycle may be viewed as qualitatively optimal or suboptimal. Their posture will be either helping or hindering overall comfort and performance through the following attributes:

Balance

A key role of optimal posture is to align the body to function and perform well in the presence of gravity. Hence, having the rider’s centre of mass balanced over the primary fulcrum point of the bicycle will help optimise muscle recruitment and handling responsiveness.

If the rider’s centre of mass is balanced over the bike, then small postural changes can be more easily deployed for the demands of different riding situations, such as climbing, sprinting, cornering, and descending.

Airway and breathing

Optimal posture contributes to the maintenance of an open (vs restricted) airway to enable full use of the lungs. A sub-optimal posture will restrict the airway, limit the mobility of the ribcage, and inhibit the action of the diaphragm. Effective gas exchange is necessary to fuel the muscles to drive the pedals.

Muscle recruitment

Postural alignment informs body position which affects muscle recruitment. We are looking for a balance of anterior and posterior muscle activity from the hips and lower limbs to drive the pedals, while minimising unnecessary or compensatory upper body muscle recruitment.

Neural Transmission

Optimal spinal alignment minimises the risk of nerve impingement to both the upper and lower limbs, supporting full neural activity which is needed for maximal muscle fibre recruitment and sensory feedback.

Efficient energy use

The summation of the above factors will reduce the amount of energy used in maintaining postural compensations, extending the time taken to reach a state of fatigue. Poor posture likely hastens the onset of fatigue for any given fitness level.

Ongoing participation

For injured or older cyclists with medically diagnosed spinal conditions, the ability to maintain optimal posture while riding is critical to being able to continue riding pain-free and without further aggravation to their condition.

Contributors to suboptimal posture

Postural self-awareness

The vast majority of cyclists are unaware of how they look and function on a bicycle, other than through the metrics provided from their cycle computer. With the exception of some high performance programs, the culture of cycling has not embraced skills-based feedback and coaching, other than the skill of getting faster by getting fitter. Many cyclists do not know how they should be situated on a bicycle, and how to align and use their body to best effect for comfort and performance.

Equipment choice

Many cyclists present with poor posture due to subconscious compensations for unsuitable equipment choices. The saddle is a frequent culprit and is a critical piece of equipment because many postural compensations result from a poorly supported pelvis. However, the list is extensive and also includes seat post setback, crank length, stem length and angle, handlebar dimensions, and most fundamentally, the underlying bike frame geometry and size.

Bike fit position

This refers primarily to saddle position (height, setback, angle) and handlebar position (reach and drop) for the cyclist. A person can present with a good position as defined by normative joint angles based on static or dynamic measurements, and yet exhibit signs of suboptimal posture.

If a fit position is determined and set up without considering posture, the rider may be locked into a position of ongoing postural compensation. If they subsequently attempt to adopt a position of improved posture, the fit position will make it harder, not easier to maintain. A ‘good fit' is not a good fit if it only takes into account position as defined by joint angles.

Foot-pedal interface

An important subset of both equipment choice and the bike fit position is the choice of cycling shoe and related internal foot support, and external cleat position and modifications. Dysfunction in the stability of the feet on the pedals can have kinetic chain ripple effects up to the pelvis and spine.

Pre-existing conditions

These include leg length differences, spinal conditions (scoliosis, spondylitis, stenosis, disc compression, fractures, and fusions), overuse injuries, and carryover effects from prior accidents or surgeries. Any of these may produce postural compensations as the body seeks the line of least resistance to operate the bicycle.

Bike fit interventions to promote optimal posture

Incorporating a postural-centric approach into an existing bike fit process may require a shift in mindset and process. The process begins with a pre-fit interview and off-bike posture, gait, and functional movement assessment, followed by an examination of the current bike presentation and set up. Once the cyclist is on the bike, begin with a global impression of their overall posture and relationship to the equipment.

If postural compensations are present, move to more specific assessments to flush out probable causes. This may include position assessments, pelvic stability, saddle pressure mapping, centre of mass balance, frontal plane knee tracking, and deeper questioning of the rider. The purpose of this information gathering phase is to build up an evidence case to present to the cyclist and to hypothesise likely interventions. This is not ignoring the cyclist’s reason for a bike fit, be it performance gains or relieving discomforts. These specific objectives or issues are addressed within a postural context.

The traditional bike fitting process follows a linear sequence of adjustments to the shoes/cleats, saddle, and then bars. A postural-centric approach takes the form of a ‘cascading triage’ model, in which the area of highest need and impact is addressed first, followed by the next most significant, and so on. In this model, an area such as the foot-pedal interface might be revisited multiple times at different stages, instead of trying to do everything at once.

The primary interventions used in the bike fit process are:

Awareness raising

First is discussing the importance and benefits of adopting an optimal posture on the bike. I liken this to being in a position of ‘athletic readiness’ in order to function and perform well. This is equally applicable to any other sport, so if I have determined the cyclist is also active in other sports, I will reference those for an analogy.

The intellectual concept is made more powerful with visuals, and the best visual is for the cyclist to see themselves on the bike via video. I primarily use the side view, but occasionally will use rear view to show pelvic instability, or front view to illustrate leg alignment. Often the cyclist does not know what to do on the bike to improve their posture, so we start off the bike.

Off-bike coaching

I will have a good idea of the person’s postural positioning potential on the bike through previous assessment of their standing posture, gait, strength, and mobility. To translate this onto the bike, I find it helps to start with a postural movement sequence off the bike. From standing, I introduce and guide the rider through hip hinging, spinal stabilisation, core, and shoulder engagement.

In addition, I want the cyclist to achieve a balanced weight distribution fore-aft, and balanced recruitment of the glutes, hamstrings, and quadriceps while in hip and knee flexion. Initially, this is done with the feet side by side, and then with one foot in front of the other to simulate being on cranks. This is done with live video feedback from the side so the person can see their movements and posture.

On-bike coaching

Back on the bike, I have the cyclist apply and practice the same techniques, principally hip hinging and by lifting and leading with the sternum to prevent excessive thoracic flexion. This may be supported with hands-on physical cuing to help rotate the pelvis, relax the back or engage the shoulders or core. I’ll have the person ride with live video feedback so they can experiment and connect what they feel with what they see. The person needs to understand where they need to be on the bike, and how to get there, and your guidance may be needed for this.

Equipment selection and positioning

At this stage, the bike fitter will be determining whether the existing fit related equipment on the bike is suitable or should be changed, as well as working to refine the rider’s position such that it supports the practice and maintenance of optimal posture. Everything is up for revision, including the bike itself, but common candidates are changes to the saddle, saddle positioning, cleat positioning, and handlebar positioning. The primary contact points are manipulated to allow the person to ride in a noncompensatory manner.

Assign homework

Work with the cyclist to find one or two mental or physical triggers that they can take away and use to cue themselves into having an optimal posture for specific riding situations (climbing, descending, cornering, etc.). Instead of climbing onto the bike and then slouching on the couch, the posture aware cyclist will focus on adopting a position of ‘athletic readiness’ and in doing so will likely enhance their performance, as well as mitigate common cycling aches and pains.

In addition to increasing proprioceptive and mental awareness, some riders will benefit from a program of exercises to improve posterior chain and spinal mobility, and core and glute strengthening and activation.

Conclusion

Advances in the accuracy and use of technology for bike fitting has swung the pendulum toward a strong focus on data collection and analytical thinking. By focusing on the cyclist’s posture, the bike fitter can blend qualitative observations together with quantitative data to achieve a superior outcome. The best bike fitting outcomes involve attention to the interactions and interdependencies of posture, position, and contact point management.

• This article is an edited version of a paper presented to the IBFI by John Higgins as a requirement for attaining Level 3 certification. John was mentored by IBFI Level 4 fitter Happy Freedman. Additional thanks to Dr. Andrea Myers for providing peer review. If you’re a Level 3 or 4 certified fitter and would like to become a mentor, email mentoring@ibfi-certification.com.