I’ve written about the purported benefits of engaging a strong yoga foot in past posts. It seems foot researchers are catching on to something yogis have been practicing for a long time. It’s called the “short-foot exercise,” but is essentially the equal of the strong yoga foot. Several recent small studies show promising benefits of the short-foot or strong yoga foot exercise for strengthening intrinsic foot architecture and improving postural stability aka balance. This is heartening as many health claims in yoga have arisen, unsubstantiated, out of various yoga lineages and proliferated through popular yoga publications and well-intentioned teachers. Proselytizing unsubstantiated health claims harms our profession.
Your feet are complex and serve many functions in stability and movement. Standing, balancing, and walking gait require the arches of your feet to deform on command as the need for stability, rigidity, flexibility, and elastic energy storage and release quickly changes depending on what you doing. Add other forms of movement you might do – run, jump, dance, hike, climb, etc. and its apparent that you need strong, flexible, mobile feet with keen ability to propriocept or sense the terrain under them. Your intrinsic foot muscles, which have all of their attachments within the foot, are considered stabilizers (as opposed to the extrinsic muscles that have attachment points both on the foot and on the lower leg and are your movers). One of the main jobs of the intrinsics is to support the four arches of your foot (medial, lateral, and two transverse) that one could envision as a half dome. It is this half dome that must deform properly in all types of movements – standing, balance, walking, running, dancing, etc.
Half dome of foot arches
*Image from McKeon article.
With each step you take, your intrinsic foot musculature acts to control deformation of this half dome of arches. When these muscles are not functioning properly because they are weak and uninnervated, your foundation is unstable and misaligned and thus abnormal compensatory movement occurs. I’ve written previously on how foot turnout and a forward pelvis can wreak havoc with your feet. Imagine what abnormal foot biomechanics in movement might do?? Several conditions immediately come to mind – plantar fasciitis, bunions, metatarsalgia, Morton’s neuroma, and pes planus or flat feet. A weak medial arch (that’s the long arch on the inside of your foot) is one possible cause of flat feet, which, if you have them, negatively impact your other weight-bearing joints with friction and subsequent degeneration. Your flat feet have weak plantar muscles that fail to function optimally in their crucial roles as shock absorbers, in gait efficiency, and as postural stabilizers, making balance difficult. And, oftentimes, they just plain hurt. If your feet are flat, your medial arch is missing, which means your half dome cannot deform to provide necessary transitions from rigidity, flexibility, and energy storage and release that propel you forward when walking or running. When your arch doesn’t store and release elastic energy in gait, you are having to work exponentially harder to move forward. Your flat feet are exhausting.
The strong yoga foot or short-foot exercise is used to reinforce the arch of the foot by strengthening the plantar muscles – the four muscle layers on the bottom of your foot, predominantly your abductor hallucis, which is the most superficial and easiest to measure of the intrinsic muscles. By contracting the foot’s intrinsic muscles, the long medial arch is shortened and its angle increased. This lift of the arch lowers the mediolateral center of pressure (the pressure on the part of your flat foot that should be arched), and increases pressure of appropriate contact areas of the foot (forefoot and heel) on the floor stimulating cutaneous and muscle receptors, which help you to right yourself in the context of balance. Essentially, a strong arch is crucial to optimal gait and balance. Research shows that the short foot exercise reduces arch collapse, improves balance ability, increases big toe flexion strength, and improves function in chronic ankle instability.
How to Perform the Short Foot Exercise
The short-foot exercise is performed by shortening the foot in a front to back direction – the first metatarsal head (aka the base of big toe; big toe mound; or ball of the foot in yoga speak) is drawn toward the heel without flexing or curling your toes. The forefoot and heel touch the floor, while the medial arch lifts.
Short foot exercise
*Image from McKeon article.
The short foot exercise can be performed either sitting or standing for improving strength, but should be practiced while standing if using this exercise to improve balance. When standing, it can be done bipedally, meaning both feet on the ground, but only one foot should be working; or unipedally – balancing on only one working foot. Placing the ankle into passive dorsiflexion by inclining the foot 30 degrees on a board or yoga wedge results in higher activation of abductor hallucis than that of the typical, neutral short foot position, possibly due to length-tension relationship in which optimal muscle length generates the greatest muscle force. The exercise is repeated 3 times for 5 seconds per rep, making one set. Sets of three reps are repeated 5 times, with two minutes of rest after every set. Alternatively, sets could be spread throughout the day.
A daily progressive program might look like this:
- Week 1 – sitting, 5 sets of 3 reps with at least two min of rest between each set
- Week 2: – bipedal, 5 sets of 3 reps with at least two min of rest between each set
- Week 3: – unipedal, 5 sets of 3 reps with at least two min of rest between each set
- Week 4: – inclined foot, 5 sets of 3 reps with at least two min of rest between each set
- Maintenance – any combination of the above
For yoga practitioners, use the strong yoga foot in Tadasana and foot balancing postures. Remember, for whole body health:
- shift your hips back when standing/balancing so that the center of your mass (your pelvis) is aligned over your knees and ankles, and heels and not over the fragile structures of your forefeet;
- engage the lateral hip muscles on the balancing leg as this strength is crucial to optimal gait and missing in most people; and
- lower your kneecaps by relaxing your quadriceps to minimize the amount of friction/degeneration in your knees.
The following studies informed this post and are available free, in full text on PubMed.
The foot core system: a new paradigm for understanding intrinsic foot muscle function. McKeon, PO et. al. Br J Sports Med. 49:290, March 21, 2014.
EMG Activity of the Abductor Hallucis Muscle during Foot Arch Exercises Using Different Weight Bearing Postures. Goo YM, Heo HJ, An DH. J Phys Ther Sci. 2014 Oct;26(10):1635-6.
The Effect of an Inclined Ankle on the Activation of the Abductor Hallucis Muscle during Short Foot Exercise.
Heo HJ, An DH. J Phys Ther Sci. 2014 Apr;26(4):619-20.
Immediate Effect of Short-foot Exercise on Dynamic Balance of Subjects with Excessively Pronated Feet.
Moon DC, Kim K, Lee SK. J Phys Ther Sci. 2014 Jan;26(1):117-9.