Your Foot and Windlass Effect in Running

The benefits of mobility and strength training for longevity cannot be understated. Not being able to get up after you’ve fallen is a real thing. In Canada, falls are the leading cause of injury-related hospitalizations and injury deaths among people aged 65 or older. Mobility training is not just beneficial for the elderly. Runners who practice stretching and strengthening benefit from balanced muscle development and lower injury rates as increased slow twitch (Type 1) muscle fibres -the very muscles that convert oxygen to produce energy and support you on longer runs, help sustain activity for long periods of time and help stabilize bones and joints. Individuals with a high oxidative capacity tend to have a lower resting heart rate and improved metabolic health.

Running in particular, requires a steady cadence to avoid injuries or repetitive strains, and if not, at least a healthy gait cycle.

Endurance training has significant advantages in maintaining neuromuscular connectivity and efficiency among older adults. Endurance training supports the preservation of muscle function and coordination. Physical fitness is crucial for sustaining everyday activities and overall quality of life as one ages. Running in particular, requires a steady cadence to avoid injuries or repetitive strains, and if not, at least a healthy gait cycle. This involves a strong core and muscles that support the hip, including glutes (medial in particular), adductors, sometimes referred to as the 4th hamstring, as well as the intrinsic muscles of the foot and ankle. Before we delve into the biomechanics of the foot, let us look at a runner’s gait cycle.

Key aspects of a runner’s gait include:

Strike: Landing on the mid-foot or slightly forward with a rolling motion. 


Stance: Quick weight transfer over the foot, with knee slightly bent and ankle flexing to absorb impact. 


Swing: Active leg swing with knee flexion, allowing for hip and knee flexion as well as efficient foot clearance. 

Float: During the float phase, neither foot is touching the ground. This is what separates running from walking, when at least one foot is always in contact with the ground. According to research published in 2018, high-performance runners spend 11 percent longer in this phase than recreational runners.


Tilt: Slight anterior (forward) tilt of the pelvis to maintain balance and forward momentum. If a runner is stuck in a posterior (backward) rotation of the pelvis (with their bum tucked under), it is the definition of poor biomechanics and injuries will likely develop.


Arm Swing and Thoracic Rotation: Opposing arm movements counterbalance the leg swing. That is where the reach comes from during your stride in a sprint. Thoracic rotation helps with breathing, prevents excessive rotation in the lower back and transfers force through the spine resulting in a more “spring loaded” propulsion.


The windlass effect helps the foot support body weight, move body weight through space, and transition from mid-stance to toe-off. 

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. That organization is called ‘the windlass effect’”. 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 compared to when you push off, or in the case of running, propel forward. During the push-off phase and dorsiflexion of the foot, the plantar fascia is pulled into a taut transition, causing the arch to rise and become more rigid. This increase in arch height and stiffness is what transmits force more efficiently from the foot to the leg, allowing for propulsion. ‘The windlass mechanism turns your foot and ankle into a biomechanical spring board’.

There are unique problems in gait biomechanics that pose a major problem and can seriously curtail or hijack the windlass effect.

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 often gets overlooked is Hallux Valgus (HV), also known as a bunion, and is one of the most common forefoot deformities. HV manifests with the proximal phalanx deviating laterally and the first metatarsal head deviating medially. Essentially, the big toe starts to drift towards the other toes and in doing so, results in the sesamoid bones shifting out (towards the midline of the body). This misalignment of the big toe puts pressure on the sesamoid bones located under the toe joint, causing inflammation and discomfort. It typically is so uncomfortable that those afflicted with this start to develop a spiralled or supinated gait in which more pressure is distributed onto the outer portion of the foot (to avoid discomfort through the “roll” or 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 (usually the quadratus lumborum) on the same side.

Key points about Sesamoid Bones and Bunions:

Location:
Both are found near the base of the big toe, with the sesamoid bones sitting directly underneath the joint. 



Function of Sesamoid Bones:
These small bones act as a pulley system, helping the big toe move smoothly and absorb shock during walking. 



Bunion impact on Sesamoid Bones:
When a bunion or inflammation of the tissue around the joint develops, the big toe is pushed out of alignment, which can put extra pressure on the sesamoid bones, potentially causing irritation and inflammation (sesamoiditis). 


Symptoms of Sesamoiditis:
Pain under the ball of the foot, tenderness at the base of the big toe, swelling, and discomfort when walking. Eventually, stiffness and an inability to dorsiflex or bend through the ball of the foot develop.




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 tight shoes with heels contribute to the development of bunions and inflammation of the joint. Regardless of pain or inefficiency concerns, if an individual does not have a sufficient “toe off”, even walking can become problematic, if not painful.

…if you cannot effectively “bend” at your toe joint, there will be negative implications in your gait biomechanics.

The peak position of the windlass mechanism in running is the mid-point between the transition from dorsi flexion to plantar flexion, which means that if you cannot effectively “bend” at your toe joint, there will be implications in your gait biomechanics. 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- efficient transfer of force through the foot and into the leg!

There are so many exercises in Pilates that not only strengthen the lower leg but also connect movements of the foot to the glutes. To get better acquainted with the incredible amount of power that you can develop in your “toe off”, stride or in developing that steady gait ideal for long distances, head on over to my YouTube channel and watch this video on “Foot Ankle” using the Wunda Chair.