Understanding the Windlass Mechanism: The Key to Better Walking and Running

The Gait Cycle

J.D. Denton describes the running mechanics of the foot as a "loose bag of bones" as it flies through the air toward the ground. He writes, ‘During that brief time on the ground, those loose bones, along with the attendant muscles, tendons, and ligaments of the foot (including that all-important plantar fascia) have to organize and transform into a rigid lever to lift you into the next period of flight. James Earls, in his essential book on gait, elaborates on this idea in an addendum to Thomas Myers’ seminal Anatomy Trains. In his holistic book, Born to Walk, Earls describes walking as a ‘series of controlled falls’. He writes, “With each step, we have to stop ourselves from falling.” The elastic energy that he describes as “metabolically cheap elastic energy” within the myofascia of the planted foot is also called ‘the windlass effect’.

The Windlass Effect

The etymology of ‘windlass effect’ has its roots in nautical language, describing a powerful winch mounted on the bow used to lower and raise the anchor. The windlass effect helps the foot support body weight, move body weight through space, and transition from mid-stance to toe-off. When your foot is at rest or standing, the intrinsic muscles of the plantar fascia are relatively slack or soft. It is at the critical point of push-off (dorsiflexion in the case of walking or running) and during the transition from heel rocking onto the forefoot, which engages the plantar fascia and causes the arch to rise and become more rigid. The increase in arch height and stiffness transmits force more efficiently from the foot to the leg, allowing for propulsion. The windlass mechanism essentially turns your foot and ankle into a biomechanical springboard. The peak position of the windlass mechanism in running is the midpoint between the transition from dorsiflexion to plantar flexion, which means that if you cannot effectively “bend” at your toe joint, there will be major implications for your gait biomechanics.

The Problem with Bunions

There are unique problems in gait biomechanics that pose a major problem and can seriously curtail or hijack the windlass effect. One common problem that is often overlooked is Hallux Valgus (HV), also known as a bunion, and it is one of the most common forefoot deformities. HV manifests with the proximal phalanx deviating laterally and the first metatarsal head deviating medially. Basically, the big toe starts to drift towards the other toes, resulting in the sesamoid bones shifting out (towards the midline of the body). This misalignment puts pressure on the sesamoid bones located under the big toe joint, causing inflammation and discomfort.

It typically is so uncomfortable that those afflicted develop a spiralled or supinated gait in which more pressure is distributed onto the outer, lateral edge of the foot to avoid discomfort through the “roll” of the dorsiflexed foot. This translation off of the big toe or “first ray” and the ensuing spiralled detour onto the longitudinal edge of the foot has implications for the entire gait, affecting not only the tracking of the knee but proper stabilization through the pelvis, derailing the windlass effect, causing all kinds of pain, often in the hips and lower back (often the quadratus lumborum) on the same side. Regardless of pain or inefficiency concerns, if an individual does not have a sufficient “toe off,” the simple act of walking can become problematic, if not extremely painful. It is estimated that about 1 in 5 people have bunions to some degree. They are more common in women than in men, and while there are risk factors such as genetics and age (more people over 40 tend to have bunions), tight shoes or the combination of tightshoes with heels contribute to the development of bunions and inflammation of the joint.

The Biomechanical Chain

The sesamoid bones act as a pulley system to guide the big toe to move smoothly and absorb shock during toe-off. The greatest stabilization happens at the combination of toe extension and plantar flexion of the ankle. And that is where the toes and the glutes connect-through intrinsic support and efficient transfer of force through the foot and into the leg. When a bunion or inflammation of the tissue around the joint develops, the big toe is pushed out of alignment, putting extra pressure on the sesamoid bones as they crowd, causing more irritation. It becomes a catch-22 situation where discomfort leads to a change in the gait cycle; derailing the mechanism and creating further discomfort along the biomechanical chain.

The Classical Pilates Solution

One way to address the pain is to ensure there is ample room for the forefoot in your footwear, as well as adopting a practice of wearing toe spreaders and massaging between the metatarsals. This reduces stiffness in surrounding joints, improving flexibility and providing a greater opportunity for the big toe to be involved in dorsiflexion. There is an exhaustive list of Pilates exercises that not only strengthen the lower leg but also connect movements of the lower leg (including the foot) to the glutes. Experienced trainers and practitioners should know how the exercises address the windlass mechanism and improve overall gait health. By understanding this mechanism and using Contrology as the lens through which we interpret movement, we not only address asymmetries and fascial restrictions but also support the development of exceptionally strong functional and biomechanical movements needed for walking and running.

Are you suffering from Achilles tendon strain, flat feet or frustrated with your stride? Book a free consultation to learn more about how Contrology can benefit your training program.

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References and Further Reading:

Earls, James. Born to Walk: Myofascial Efficiency and the Body in Movement. North Atlantic Books, 2014.

Myers, Thomas W. Anatomy Trains: Myofascial Meridians for Manual and Movement Therapists. 3rd ed., Churchill Livingstone/Elsevier, 2014.