Ankle mobility

The ankle is a joint formed where the tibia and fibula meet the talus beneath them. This joint produces dorsiflexion, which lifts the toes upward, and plantar flexion, which points them downward. During walking, the foot moves forward and the shin tilts over the foot. Sufficient dorsiflexion allows the walking motion to flow naturally. The same applies when going up and down stairs, squatting down, or running.

Several tissues work together to determine dorsiflexion range. The structural shape of the ankle joint itself, the length of the calf muscles (gastrocnemius and soleus) and the Achilles tendon, and the joint capsule and surrounding tissues all have an influence. So even when people feel that their ankles are stiff, the main location of the pulling sensation varies from person to person.

A concept often discussed alongside ankle mobility is the windlass mechanism. When the big toe bends upward, the plantar fascia on the sole tightens as though being wound up, raising the foot's arch and turning the foot into a rigid lever. This mechanism operates at the final moment as the foot leaves the ground during walking, increasing foot stability. One explanation is that when calf stiffness limits the dorsiflexion angle, the fascia on the sole takes on a greater share of the load. This is why dorsiflexion of less than 10 degrees with the knee straight is one of the factors discussed in connection with plantar fasciitis.

An assessment that dorsiflexion is “limited” means different things depending on the tools and conditions used to measure it. Results vary depending on whether you are barefoot or wearing shoes, sitting or standing, and whether your knee is bent or straight. Measuring with the knee straight reflects more of the gastrocnemius muscle's influence, while measuring with the knee bent makes the influence of the soleus and the joint itself more prominent.

There are also several measurement methods. The joint angle may be measured with a goniometer, or the distance from the wall to the toes may be measured. Even for the same person, results can vary slightly between morning and evening, when the body is warm or cold, and depending on who takes the measurement. It is therefore best to treat a single measurement as a reference for that day and take repeated measurements under consistent conditions to track changes over time.

During complex movements such as walking or squatting down, the knees, hips, and toes move along with the ankles. So if your ankle appears to bend less during a particular movement, it is helpful to check the movement of the surrounding joints as well, rather than looking only at the ankle joint.

• When I squat down, my heels lift or I feel as though I might fall backward.
• During a squat, my knees do not move forward toward my toes easily.
• When I go down stairs, the front of my ankle feels completely blocked.
• After running, I feel a particularly strong pulling sensation in my calves and Achilles tendons.

Check it at a wall — Stand barefoot facing a wall with one foot in front. Keeping your heel on the floor, slowly push your knee toward the wall. Note the greatest distance between your toes and the wall at which your knee can still touch the wall, then compare it again a few weeks later using the same method. Testing each foot also lets you check for differences between the two sides.

Stretch your calves — Place your hands against a wall, keep your back leg straight, and press its heel into the floor to stretch the gastrocnemius. Bending the back knee slightly stretches the soleus. Hold for about 20–30 seconds at a time, with a pulling sensation but no pain.

Practice squatting down — Holding a wall or doorknob, slowly lower yourself and rise again while keeping your heels down, practicing using your ankle's bending range a little at a time.

Loosen your feet and ankles — Move your ankles in large circles and bend your toes upward to gently loosen the plantar fascia, helping the whole foot feel more supple.

Check your shoes — Wearing high-heeled shoes for long periods can make the calves prone to becoming stiff in a shortened position. Try spending part of the day in shoes with lower heels.