Foot biomechanics

Foot biomechanics

An interesting biomechanical issue unpacked this week.

In our performance enhancement session with a runner, we were discussing foot biomechanics and past injuries. These included tibial stress fractures, navicular fractures, tight calves and plantar fasciitis.


Looking at the foot there was a degree of (more than normal) overpronation, leading to a lack of use of the windlass mechanism. This is where the big toe flexes and tightens the plantar fascia, making the foot into a rigid lever.  This allows a firm surface to push off. Lack of use of the windlass means the foot is less rigid, and a firm base for propulsion is not available. Consequently, the calves are having to work harder than normal to provide a propulsive force. This is one reason calves tighten up when running.

Overpronation and tight calf can cause a functional elongation of the plantar fascia and bowing of the Achilles tendon, which can lead inflammation at the tendon insertion and tendinosis. At the calcaneal insertion of the fascia, it can cause plantar fasciitis.

windlass mechanism

Stiff Big Toe

In addition to overpronation, the foot had a reduction in flexion of the big toe. The effect of reduced range of flexion at the big toe continues up the biomechanical chain. It prevents the hip from extending fully, reducing the elastic recoil of hip structures. Along with the associated issues; reduces extensor power, encouraging hip flexors to pull through rather than hip extensors to push off. The over worked hip flexors become tight, causing anterior hip pain. Also, due to their attachment on the anterior surfaces of the five lumbar vertebrae, tight hip flexors can lead to hyperextension in running and low back pain.

The human body is a kinetic chain. What happens at one joint will have a knock on effect at another joint.Correcting the overpronation and mobilising the big toe joint, allowed the higher biomechanical chain to be more effective and reduced stress and strain through the lower limb, solving a number of recurring issues in one go!

2 Responses

  1. Hi, I have plantar, I’m not a runner or an athlete, I walk a lot. How much does an appointment cost? I would like to know what to do to help this. I have insoles but am not sure if I should be doing anything else, exercise? Strengthening certain muscles? I have had hardly any help from GP for this only in the beginning injections, which only mask it.
    Thank you.
    Samantha Bowles

    1. Hi Samantha,

      Thank you for replying to my post on plantar fasciitis on the Loughborough Physio Clinic website. I must offer my apologies for not replying sooner. It is a new website and I realise that comments are not automatically flagged, so I need to sort this problem as a week to reply is not acceptable!

      Can I suggest that we see for for a one off appointment? With myself that would be £60.I can look at your feet and show you strapping to reduce pain day to day and also stretches and tips to help. You can go and try them and see how you progress. Most people improve with this treatment.If you have any questions etc we can talk and email so you are in contact with me regularly to help.

      If it doesn’t settle we have a Shockwave Therapy machine, which all of the recent evidence shows as having good results with chronic plantar fasciitis. I can talk about it with you, but you need 5 sessions and they are £60 a session. I’d ensure you have done all the basic treatment before we consider the Shockwave.

      Any questions please feel free to contact me on this email or the main work email ( Hope this helps and again apologies for the delay.

      Kind regards

      Jo Hartshorn


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