It is estimated that 20-30% of the general population suffer from flat feet. Flat feet is a type of foot posture that occurs when the inner arch of the foot has collapsed. As a result, the bottom of the foot is in complete contact with the floor with a loss of arch present. This type of foot posture is also referred to as Fallen Arches, Overpronated Feet and Pes Planus.
In this post we'll cover types of flat feet, factors that affect flat feet, how to test for it and, finally, we'll see some releasing, stretching, strengthening and stability/balance exercises.
Our feet are responsible for three main functions that control the body's optimal alignment:
1: The feet (specifically the arch and the heel) act as a shock absorber
2: The feet provide support for the body's weight, evenly distributing the pressure over the whole foot
3: The feet are designed to bear the full weight of the body.
Although it is completely normal for the foot's arch to flatten somewhat when it bears weight, problems occur when this movement is excessive, uncontrolled or the foot begins to get stuck in this position. Flat feet are a common cause of foot, ankle, leg and back pain due to insufficient support of the body's weight when standing or with movement.
Why it's important to have an arch
When the arch is no longer present, it throws off the foot's ability to buffer your weight and provide stability.
Some people with flat feet may not experience pain. However, over time flat feet can cause undue stress to the foot’s muscles, joint, bone and tendons, and cause swelling along the arch and ankle. The resulting instability will also lead to an increased risk of knee, hip, and lower back pain. (1, 2)
Types of flat feet
Structural Flat Feet: Due to genetics, one or both parents have flat feet.
Functional Flat Feet: An adaptation to poor postural habits, poor control at the toes, feet and/or ankles and weak or tight foot muscles.
Is it Structural or Functional?
You can test for this yourself easily at home: If you are standing up and the arch is present but then you sit or lay down and the arch is not present then this indicates you have functional flat feet. Otherwise you would see no changes when comparing the two situations.
Structural flat feet would show the foot arch being physically flat no matter what (sitting, lying or standing). This is due to the formation of the bone/joint.
Click here to jump to 3 different tests you can perform to test for flat feet.
What factors affect flat feet?
One or both parents have this foot posture so the formation of the bone/joint results in the arch being physically flat.
Increase in bodyweight (overweight)
The feet are the base and connector to the ground, when we have extra weight being placed on the feet it alters the foot mechanics and places strain on the arches.
Improper use of footwear (now or in childhood)
Emerging research has shown that shoe wearing contribute to flat feet (3). A study found that children who wore shoes were 3x more likely to have flat feet than those who went barefoot (4). This is because habitual shoe wear does change the shape and biomechanics of the foot.
Being barefoot distributes the pressure more evenly. I highly recommend being barefoot as often as possible. If you have children, I also recommend having them walk around barefoot. Not only will it help with the correct formation of the foot mechanics, it will also allow them to feel more stable on the ground.
There are over 7,000 nerve endings in each foot and these proprioceptors give our feet ground feedback and help us to feel balanced and stable. This is why, when you put a child who is learning to walk in shoes they become instantly more unsteady than when they are barefoot. Their ability to sense the ground through these sensory neurons are taken away.
Flat feet is a key factor in poor posture as the muscles, joints and tendons will become either weak or tight. The ankles lose mobility, the calf muscles become tight, the knees tend to track inwards which can lead to ACL or MCL injuries (5, 6) and knee pain. The leg muscles are also deeply effected and flat feet has been show to lead to IT band syndrome (7), hip impingement (8) and weakened glutes (9).
Incorrect form/technique in sports
When walking, biking or running improper form can lead to pain, discomfort and injuries.
Flat feet will present problems with the knees, since flat feet place all the pressure towards the inside of the foot, this means the tibia and femur bones internally rotate. As this occurs, the muscles of the leg become effected and the knees begin to move inwards (knee valgus).
You will see this when you walk (watch my How To Walk video), when you bike you will notice the knees move inwards towards each other, creating tightness in the adductors, and when running, the knees will also track inwards, leading to knee pain, issues with the TFL and IT Band and the quadriceps.
This is why taking the time to become aware of your postural habits and leaning the correct form is critical to pain-free movement.
Testing for Flat Feet
Now that you know what factors contribute to having flat feet, as well as the importance of having an arch, we'll cover different ways to test for flat feet at home. If you prefer to watch this in video format, watch here:
I recommend the following 3 tests:
Test 1: Stand sideways in front of a mirror without your socks on. Take a look at the arch, is it present? Can you see a small gap underneath the arch or is the foot flat to the ground?
Test 2: Stand upright and close your eyes. Feel the weight of your body on your feet and pay attention to where you feel the pressure. Is it on mostly on the heels? Is it on the outer part of the foot? Do you feel the majority of the pressure on the toes or ball of the foot?
If you have flat feet you will feel a lot of tension towards the inner arch. I would also suggest seeing if you feel the pressure on one foot more than the other. This would indicate that there is an asymmetrical difference. Perhaps you lean towards one side and/or you have one hip lower than the other.
As a reference: The picture shows what is known as the Foot Tripod and it is a very useful way of visualising how the foot connects to the ground. The three points of contact should be:
Centre of the heel
Base of the small toe
Base of the big toe
When the weight is evenly distributed over these points it gives stability to the foot. Learning how to feel these contact points is the key to improving flat feet.
Test 3: Place your index finger underneath the arch (or have someone do it for you as you stand up). As a good rule of thumb, you are aiming for the fingertip (the first crease line on the index finger) to reach under the arch. Check both sides and check for any differences. If one side is flatter than the other (i.e you couldn't get to the crease-line on one side but you could on the other) then this is a sign that you may have a rotated pelvis. The pelvis will be rotated away from the flat foot. I would also recommend performing this test on one foot so you can check to see what happens when stability and balance is tested.
So now you know that you are a flat footer, how do you proceed?
(If you would prefer to watch this in video format, click here)
We will address flat feet using 4 steps:
The goal is to release the knots first before doing anything else.
This is the area underneath the arch.
Place your foot on a massage/tennis/golf ball.
Apply pressure on the ball
Roll your foot up/down, focusing on the arch and the lateral side of the arch
It will feel painful but it's important to breathe into it. Reduce the pressure if it feels unbearable
Time: 1-3 minutes
*Note that the tennis ball will be the most bearable at first, then increase the hardness of the ball, leading up to a golf ball.
Lateral Calf Muscle/ Peroneal
This muscle is located on the outer part of the lower leg (shin)
Place the ball on the outer portion of the lower leg
Apply pressure over the ball using your hand
Go over the whole area and find the most painful spots to release
Use a circular motion with the ankle to increase the release
Time: 1-3 minute
Sit on the floor with your leg straight
Place the Achilles tendon on the ball.
Apply the pressure downwards, into the floor
Slowly rock your foot from side to side.
Time: 1-3 minutes
Once the tissue and fascia is loosened up we want to stretch the tight muscles and associated fascial structures.
Place the toes and ball of the foot against the wall with the heel on the ground
Keep the knee completely straight and lean towards the wall
Aim to feel a deep stretch in your calf muscle.
Hold for 60 seconds, then switch sides
Soleus and Ankle Stretch
Get into a lunge position next to the wall
Bend the ankle at the front as much as you can, until it just touches the wall
You may need to move your foot further away from the wall to get a deeper stretch
Aim to feel a deep stretch in your calf muscle and your ankle joint
Make sure the heel remains on the floor otherwise you will feel this in your knee
Hold for 60 seconds, then switch sides
When releasing and stretching is complete, the goal is to strengthen the foot muscles that encourage the arch in the feet (the Planter muscles, the Tibialis Posterior and Anterior).
Foot Towel Grabs
These help activate the muscles of the arch.
Stand with your foot over a towel
Use the toes and the bottom of your foot to scrunch the towel up
Drag the bottom of your big toe back towards the heel
Aim to feel a strong contraction in the muscles underneath the foot (it may feel like it's going to cramp)
Time: Perform 20 times or for 1-2 minutes
Stand on top of a yoga block or a high book(s)
Place a tennis ball between the ankles and push against it throughout the movement
Drop the heels down to the floor until you feel a very deep stretch in the ankle joint and calf
Perform a calf raise by coming up onto the toes and squeezing the calf muscle
Keep the Achilles tendon vertical throughout the movement by not letting the ankles roll
Time: Perform 20 repetitions
The final step involves effectively training the balance response.
Single Leg Star Balance
Place the hands on the hips and balance on one leg
Try to keep the hips in line (don't let the hip drop or hike up)
Activate the arch muscles by keeping the ankle from rolling in and try to maintain an arch
Whilst balancing on one leg tape the other foot to the ground away from your standing leg
Gently tap the big toe to the floor (in different directions - think about drawing the points of a star - forward, sideways and behind you)
Keep the pelvis level (this is worth repeating twice)
Time: Perform for 60 seconds per side
Progress the movement by tapping the foot further away from you.
Addressing other areas affected by Flat Feet
There are many additional areas to cover.
It is important that you also address the knee, hips and muscles surrounding the knees and hips.
Start with the above releases, stretches, strengthening and balance improvement.
Improve Hip Rotation: Remember when I said that flat feet leads to knee valgus femur (leg bone) internal rotation well this effects the hip joint too. The hips needs to be mobilised. Include exercises that improve hip external rotation. I recommend the Modified Elevated Pigeon Stretch.
Improve Anterior Hip Mobility: Tightness or reduced flexibility in the hip flexor muscles that cross the front of the pelvis contribute to issues with flat feet and Anterior Pelvic Tilt. I recommend the Wall Quad Stretch. This can be an intense stretch so prioritise the back being straight and aim to feel a stretch in the quadricep and front of the hip.
Strengthen the Gluteal Muscles:
Since the leg is rotated inwards and adduction is occurring the glute medius doesn't function and cannot be activated properly. This is because the glute medius is the prime mover of hip external rotation (the opposite of the inward leg rotation posture), the glute medius also abducts the hip (the opposite of adduction, which is happening to the knees with flat feet).
Note: adduction is the action of bringing the leg towards the centre of the body (think adding) whilst abduction is taking the leg away from the centreline of the body.
Therefore, we must strengthen the glute medius. I recommend performing X-Band Walks and Monster Walks. I recommend strengthening all 3 major glute muscles (Medius, Minimus and Maximus). To strengthen the gluteus maximus perform Glute Bridges and for the Minimus do Side Clams.
Walking: If you aren't aware of your walking posture yet, check out my popular "How to Walk Correctly" YT video. When walking, make sure to point the feet/toes directly forward. This is so important and I can't stress it enough. Don't let the feet point towards each other and don't let them point outwards (aka duck feet).
Toes pointing in [not ideal] Feet Forward [Ideal] Toes pointing out [not ideal]
This simple cue, of keeping the toes pointing directly forward, whilst also being mindful of the Foot Tripod [3 points of contact] will go along way towards ensuring you are performing habitual movements well.
So if you or someone you know are concerned about flat feet, consider the role it plays in posture, movement and pain. Flat feet is certainly something to address, though it's important to use a multi-factoral approach.
Simply focusing on rebuilding the arch would mean neglecting other areas (mentioned above) that need to be addressed, including the rest of the leg, the knee and the hips.
It's important to look after your foot and arch specifically, however, there could possibly be an inherent limit on your capacity to see sustainable, long-term change in the future if you are dealing with structural flat feet or if this is an issue that has plagued you for many many years.
Ensure you focus on the broader mechanical issues associated with the arch collapsing in the first place (the arch is the symptom of a larger problem that needs to be addressed) and at the very least bring awareness to your habitual habits and how they translate to your daily life and exercise.
By approaching this comprehensively, as outlined above, you have a real possibility of solving this issue for good.
I hope you've found this post helpful,
1. Flat Feet Are Associated With Knee Pain and Cartilage Damage in Older Adults https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3087845/
2. The Prevalence and Factors Associated with Low Back Pain Among People with Flat Feet
3. The effects of habitual footwear use: foot shape and function in native barefoot walkers https://www.tandfonline.com/doi/abs/10.1080/19424280903386411#.UdPG9PmG18E
4. The influence of footwear on the prevalence of flat foot. A survey of 2300 children https://pubmed.ncbi.nlm.nih.gov/1624509/
5. Is chronic ACL tear a cause of adult acquired flat foot?https://www.researchgate.net/publication/333850696_Is_chronic_ACL_tear_a_cause_of_adult_acquired_flat_foot
6. Relationship of Anterior Knee Pain and Flat foot: A Cross-Sectional Study https://www.researchgate.net/publication/349952780_Relationship_of_Anterior_Knee_Pain_and_Flat_foot_A_Cross-Sectional_Study
7. Reduction of Foot Overpronation to Improve Iliotibial Band Syndrome in Runners https://www.researchgate.net/publication/326178979_Reduction_of_Foot_Overpronation_to_Improve_Iliotibial_Band_Syndrome_in_Runners_A_Case_Series
8. Associations of Foot Posture and Function to Lower Extremity Pain https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4039193/
9. Effectiveness of gluteal muscle strengthening on flat foot https://www.researchgate.net/publication/318026992_Effectiveness_of_gluteal_muscle_strengthening_on_flat_foot