CLIMBING SIMULATION IN BIKE FIT SESSIONS - WHY IT MATTERS

Over the last three years the fit process I've used has been one of functional testing. This is effectively a process of positioning riders by way of analysing the way they function on the bike. The way riders function on a bike is determined by the following:

- condition (physical state at that point in time)

- position (how they've positioned themselves on the bike)

- environment (the terrain they're on and how it affects what they do on the bike)

The challenge of a traditional (measurement based) fit session performed on either a bike on a turbo or on a sizing jig, is that the environment is to some degree quite synthetic as the bike is on a very stiff platform and (usually) on a flat surface.

In order to create or emulate better the conditions riders face on the road, the bike has to become a more fluid unit, and the fit environment one which more closely resembles the open road.

Three years ago I began using tests on the sizing jig which emulated as much as possible what riders do and experience when climbing hills. However, the thing I missed the most was an actual hill to see the riders riding on. This is important because a lot of things change when a cyclist begins climbing;

- muscles recruit in a different way

- the handlebar elevates and thus changes the way the rider interacts with them

- the saddle tilts backwards potentially creating a less supportive platform

And when the cyclist stands up on the pedals there are more implications;

- the effective reach of the bars is diminished, potentially causing the knees to knock them

- the height of the bars is raised potentially making them too high for very steep inclines

- the exercise of standing can also be negatively affected by a saddle which is too far back, or by a bar which is too far away, causing the rider to waste energy and effort in making the transition

So this brings me to the subject of the elevating fit platform. My aim in building the platform was to be able to not only see the rider on a slope, but also to see how that rider acclimatised to that slope, ie how they adjusted as the slope increased. So the elevating platform was built with an electric motor which could be activated from a distance so that I could watch the riders whilst they “engaged with the hill”.

Why does all this matter? Well, if these particular things aren't addressed in a fit session they will still be experienced outdoors. If a fitter overlooks what could be a potentially challenging “effect” for a rider on a hill, that fitter has not fully optimised the rider's position.

It's still early days though, and understanding better the differing challenges riders face on hills is one which will unfold over time. The test protocol is not yet perfect but it's certainly much closer to real life riding than it was before. Hopefully updates won't be too far behind…

See how it was constructed below.

Ronan Descy

 

 

 

 

 

Ronan DescyComment