Written By: Paul Langer, DPM — Superfeet Wellness Panel Member. Paul Langer is a sports medicine podiatrist who treats athletes of all abilities at Twin Cities Orthopedics in Minneapolis, Minnesota. He is the author of Great Feet For Life and lectures internationally on the topics of lower extremity health and footwear.
Plantar fasciitis (PF) is what I often refer to as a nuisance injury. At first, it’s rarely painful enough to stop someone in their tracks. But, it can just keep hanging on and gradually worsen over time until it becomes debilitating.
Many times very simple treatments go a long way not only in resolving PF but also in preventing recurrence. Fortunately, 80-90% of people can resolve their symptoms by doing some exercises and supporting the arch with insoles [i].
Common Causes of Plantar Fasciitis
The plantar fascia is a ligament that originates at the bottom of the calcaneus (heel bone) and extends to the bases of the phalangeal bones of the toes. The plantar fascia is the most important non-muscular structure that supports and stabilizes the arch.
The plantar fascia is under strain when we are standing flat footed but also subjected to even higher strain when our heel lifts and transfers weight to the forefoot in gait. If the plantar fascia is subjected to excessive or repetitive strain it will become injured. It is important to understand that load is highest on the plantar fascia not when the heel hits the ground, but while the heel is raising. For the vast majority who suffer from it, PF is strain problem, not an impact problem — that is why heel cushioning rarely helps.
Most people take between 8,000-10,000 steps each day just for everyday activities. Walkers take roughly 2,000 steps per mile while runners take 1,000-1,500. For a number of reasons these steps can also begin to overload the plantar fascia and cause strain.
Who Can Get Plantar Fasciitis?
PF is a unique injury in that it commonly affects young athletes but just as commonly affects older sedentary individuals, and almost anyone in between. Risk factors for plantar fasciitis include: obesity, limited ankle range-of motion, increasing activity, jobs that require long periods of weight bearing activity and improper footwear. For some, there are no easily identifiable causative factors.
There are many theories about why PF is so common. Some speculate that it is due to weakened foot muscles from wearing shoes. Others point to the artificially hard and flat surfaces such as concrete and asphalt which are more common than ever before.
Symptoms of Plantar Fasciitis
The most common complaint or symptom of plantar fasciitis is heel pain, especially after arising from bed or sitting. Pain usually improves gradually with walking only to return again later. Runners often state that they have no pain during their workout.
Variations of PF pain include pain that radiates into the arch, and pain that worsens as the day progresses. PF does not cause ankle, lower leg or forefoot pain but because PF is so common, many individuals misdiagnose themselves with this condition. X-rays may show a bone spur but this does not often affect the prognosis or treatment.
Best Insoles for Plantar Fasciitis
Those suffering with PF often ask which shoe or insole is “best for plantar fasciitis?” Of course, there is not one single magical shoe or insole that cures plantar fasciitis for all.
Start with footwear: focus on finding comfortable footwear. Insoles work great for those who are already in an appropriate shoe. I recommend insoles be selected based on comfort but emphasize that firm insoles relieve tension on the fascia better than cushioned insoles [ii].
Stretching Exercises for Plantar Fasciitis Relief
Stretching exercises that isolate the arch and calf have been shown to help reduce pain of PF[iii].
Calf Stretch (and Strengthener)
Calf stretches can be done by extending one leg behind you. While keeping both feet flat on the ground, point the toes straight ahead and lean forward, using a wall or tree for balance until tension is felt in the calf muscles. This should be held for 30 seconds and repeated three times with the knee straight and then three times with the knee slightly bent. Adding in calf strengthening exercises (good to do whether you are injured or not) like heel raises not only strengthen but also improve flexibility.
Seated Plantar Fasciitis Stretch
Plantar fascia stretches can be done from a seated position by crossing the leg and resting the foot to be stretched on the opposite knee. Next, pull the toes back until tension is felt in arch and/or heel. Hold stretch for 10 seconds while massaging the tender and/or tight area of the plantar fascia with the opposite hand. Repeat 10 times. Do one set of 10, three times each day.
Intrinsic Muscle Strengthening Exercises for Plantar Fasciitis
It is only recently that we have started to appreciate the importance of the intrinsic muscles (IMs) of the foot. IMs describe the small muscles the originate in the feet and provide stability and support. A theory proposed in 2014 equated the IMs of the feet to the core muscles of the pelvis [i]. Just as inhibition and weakness of the pelvic stabilizing core muscles can contribute to low back, knee and hip pain, the authors proposed that inhibition and weakness of the IMs can contribute to foot and ankle pain. Keep in mind that this theory that has not been fully validated. But, for those who treat foot and ankle injuries, it makes sense that having strong intrinsic muscles is an important part of not only treating injuries but also preventing them.
Note: muscles can not only become weak but they can also become inhibited, meaning the muscles may have adequate strength but are poorly activated so they do not fire properly. Your feet touch the ground for about a second when walking and less than half a second when running so any delay in firing can contribute to problems.
For those who are experiencing plantar fasciitis, the following exercises can be done daily to help strengthen the IMs until pain free, and then 2-3 times per week for maintenance:
Intrinsic muscles can be activated by doing “Toe Yoga”. Begin by standing barefoot, press the big toe into the ground while raising the lesser toes. Hold for 2-3 seconds then repeat 10 times. Then do the opposite. Press the small toes into the ground while raising the big toe. Do this daily. For some, it is difficult to do at first and then becomes much easier as the muscles become more activated. You should not see any movement in the ankles or knees when you do this. The only movement should be in the toes and arch.
Short Foot Exercise
The “short foot” exercise is another method to activate and strengthen the IMs. Place the foot flat on the ground and pull the toes back towards the heel without curling the toes up or down. Essentially you are making the foot shorter by contracting the muscles that raise the arch and pull the forefoot closer to the heel. This exercise should be done from a seated position first and then once it becomes easy should be done weightbearing. This exercise can be done either barefoot or in shoes and can be done randomly throughout the day.
A more playful way to activate and strengthen the IMs along with the EMs is to spend 1 to 5 minutes using your toes to pick up a small, soft ball.
For approximately 20-50% of people PF can recur so they need to make note of which exercises and insoles work best for them and employ them when symptoms flare.
Like most overuse injuries, the longer PF persists the more difficult it to resolve so recognizing it and treating it is best done sooner than later.
[i] Pfeffer, G.B., 1997. The conservative management of plantar fasciitis: a prospective randomised multicentre outcome study. Presented at the 27th Annual Meeting of the AOFAS, February 16th 1997 San Francisco, CA.
[ii] Kogler, G. F., S. E. Solomonidis, and J. P. Paul. "Biomechanics of longitudinal arch support mechanisms in foot orthoses and their effect on plantar aponeurosis strain." Clinical Biomechanics 11, no. 5 (1996): 243-252.
[iii] Digiovanni, Benedict F., et al. "Plantar fascia-specific stretching exercise improves outcomes in patients with chronic plantar fasciitis." J Bone Joint Surg Am 88.8 (2006): 1775-1781.
[iv] McKeon, Patrick O., et al. "The foot core system: a new paradigm for understanding intrinsic foot muscle function." British journal of sports medicine (2014): bjsports-2013.