WHY BIKEFITTERS SHOULDN’T CHEW THEIR NAILS

My index finger nail is one of my most commonly used fitting tools.  If it isn’t long enough it won’t do its job.  That job is to find the joint space of the 1st and 5th MTP joints; i.e, the joint space of the base knuckle of the big toe (ball of the foot) and small toe respectively.

Once a client interview and off bike assessment is completed, about 70% of the remaining time is spent on the feet in one way or another.  There is a lot of ground to cover with the feet:

• The functioning of the feedback loop between central nervous system and feet has to be clarified and optimised
• Optimal cant of each foot has to be determined
• Optimal degree of arch support has to be determined
• If necessary, and it often is, the optimal degree of shimming needs to be determined

But before any of that occurs, the fitter needs a reference point on the outside of the shoe as to where the foot is inside the shoe.  I’ve used a variety of methods, all of which have merit, but the simplest, most foolproof and most repeatable method was shown to me by a tall, drawlin’ Texan named Jerry Gerlich of Castle Hill Fitness in Austin.  (http://www.castlehillfitness.com/cycling.php)

Have your client stand barefooted on a hard surface.  Using the index fingernail, feel for the joint space of the 1st (and if you are me, also the 5th MTP) joint.  It is usually in the approximate centre of the bulge of the bony protrusion of the joint but there is a lot of variability in how obvious it will be.  If you are not certain, press in with the nail and leave an indent in the skin.  Then place the tip of a pen in that indent at the vertical midpoint.  Gently dorsiflex the toe.

Did the pen tip move?

If yes, you have not found the joint centre so try again with the fingernail.  If no, then you’ve found it and can mark the point with a short vertical line with a fine pen.

Now tape a cable end crimp to that mark and ask the client to put their shoe on without a sock.  Feel for the protrusion of the crimp in the upper of the shoe and mark it with a fine marker pen.

Now repeat on the other foot.  If the nature of the shoe upper makes it hard to feel a cable end crimp, use the knot off a medium size zip tie as they are larger and protrude further making them easier to feel through the shoe upper.

Once done, place your shoe in the pedal of your bike (without your foot in the shoe) on an indoor trainer. Move to the other side of the bike and using a T square measure the horizontal distance between the mark you have placed on your shoe and the centre of the pedal axle with crank forward and horizontal and shoe levelled between where the sole joins the upper at mid heel and where the sole joins the upper in mid forefoot.. Measure at both extremes of  shoe in pedal rotational movement (heel in / heel out) and halve the difference. You now know your cleat position relative to the centre of the joint axis of your 1st MTP joint!

What ever your philosophy of cleat positioning (all you wish know about cleat positioning here), this is a simple, accurate way to establish a reference point on the outside of the shoe.

See this video for more:  http://vimeo.com/9589645, and don’t chew your nails.  You’re damaging a valuable tool!

Have fun.

Note: Often, more specific answers to your questions can be found in the Comments below or in the eBooks section and FAQ page.

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