1. What Do the 26 Bones in Each Foot Do Besides Help You Stand?
The bones in your foot are divided into three main groups: the tarsals (the cluster of bones from the heel to the middle of the foot), the metatarsals (the long bones supporting the arch), and the phalanges (the toe bones) [2]. With 26 bones in one foot, that makes 52 for both feet. If an adult has approximately 200 bones in total, then 52 divided by 200 is about 26%, or roughly one-quarter of all bones [1]. However, this count can change depending on how you count. Some sources include small "sesamoid" bones, bringing the total to 28 per foot [2]. Because of this variation, it is safer to say there are "about 26" bones in each foot.
Why does having many small bones matter? The foot performs five main jobs: supporting the body, cushioning the impact of landing, pushing off the ground, sensing the surface, and helping return blood to the heart. This article focuses on how the arches cushion landings and help you push off.
2. How the Arch of Your Foot Cushions Each Landing
The hollowed-out middle part of your sole is called the arch. It is not just one curve; there are three arches: the inner longitudinal arch (the main arch), the outer longitudinal arch, and the transverse arch across the width of the foot [3]. These shapes are held together by bones and the plantar fascia, a tough band of tissue on the sole. They form a structure called a truss, which is a combination of triangles. When your body weight presses down, the plantar fascia stretches slightly, and the arch lowers a bit. This flexing action acts as a cushion, softening the shock of landing [3]. Your foot accepts the impact by changing its shape slightly.
When does this arch develop? A study from Tokyo suggests that the foot arch is recognized in most children by about age 4. Even newborns have a low arch [4]. However, other general guides say the arch approaches adult levels at ages 6–7 or 8–10 [4]. Because there are different theories and no single fixed age, we cannot say exactly when the arch is "complete." This flexible arch is useful for landing, but pushing off requires stiffness. How do softness and stiffness coexist?
3. How Bending Your Big Toe Turns Your Foot into a Rigid Lever
When you walk, your foot finally pushes against the ground to move your body forward. At this moment, your big toe bends upward. As the toe bends, it pulls the plantar fascia like a winch, raising the arch. This makes the whole foot rigid, creating a lever that generates the force to push off [5]. This mechanism is called the "windlass mechanism," named after a winding machine. So, the same foot changes its nature: it flexes to cushion landings and stiffens to push off.
However, the role of this mechanism might be more limited when running than when walking. A study by Takabayashi et al. found that the peak angle of big toe extension while running was significantly lower than while walking. This study involved 9 healthy men, so it is not yet certain that the role is small in all cases [5]. If the windlass is less active when running, what is the foot doing then? The answer lies in the arch acting like a spring.
4. How the Arch Compresses and Rebounds Like a Spring When You Run
It is thought that the foot arch acts like a spring, compressing and rebounding during running. Researchers tested this using special insoles that almost completely stopped the arch from compressing [6]. When participants ran at about 9.7 km/h (2.7 m/s) with the arch compression reduced by about 80%, their body used 6.0% more energy. This suggests that the body had to work harder because the spring-like compression was blocked [6].
It is important to note the conditions. The energy increase happened when running on flat ground at a moderate speed. It did not increase when walking or running up a gentle 3° slope [6]. Also, the 6% figure applies only when using special insoles that stop arch compression; it does not mean you lose 6% energy just by wearing normal shoes.
The arch is not the only spring. Long tendons such as the Achilles tendon also store elastic energy, which helps the muscles when you run or jump. In one report on repeated hopping, elastic energy provided about 34% of the work done in the shortening phase [7]. That 34% is a value for hopping, so it cannot be applied directly to walking or running.
5. How the Skin on Your Sole Senses the Ground
If you walk barefoot, you can feel the cold floor or the grit of sand. This is because the skin on your sole has sensory structures called mechanoreceptors, which detect pressure and contact [8]. A study by Kennedy and Inglis recorded signals from the tibial nerve in 13 people and identified 104 receptors in the sole. About 57% of these were the type that react quickly to changes in touch. These receptors are spread over a wide area of the sole. Note that 104 is the number recorded in the study, not the total number of receptors in a foot [8].
This sense is linked to balance. In a study at Nagasaki University, cooling the soles of 10 healthy adults with ice water lowered their sensation. As a result, the sway of their center of gravity while standing increased significantly [9]. However, the force from the floor while walking did not change much. This does not mean foot sensation is unnecessary for walking; it simply shows the specific effect on standing balance.
6. How Your Calf Muscles Pump Blood from Your Feet Back to Your Heart
Your feet are the farthest part of your body from your heart. When you stand, blood pools in your feet and must be pushed back up against gravity. The calf muscles help with this. When you walk, the calf muscles contract and squeeze the veins in your legs. Each time the muscles contract, they push blood back toward the heart [10]. This is called the muscle pump action.
This is why the calf is often called the "second heart." However, this is just a nickname [11]. The calf does not replace the heart; it acts as a helper to return blood from the feet. So far, we have covered the foot’s five jobs: supporting, cushioning, pushing, sensing, and helping return blood.
7. Two Simple Ways to Check Your Big Toe and Calf Yourself
You can try two simple things today. First, sit in a chair and take off your shoes. Slowly bend your big toe upward with your hand. Stop immediately if it hurts. Look and feel to see if the inner arch tightens or if the hollow changes shape. This lets you see the windlass mechanism in your own foot.
Second, hold a wall and stand on your tiptoes. Touch your calf with your other hand and feel the muscle harden. This is the muscle helping to return blood.
The next question is: what is each of the 26 bones doing? The names and positions of individual foot bones are listed in anatomy resources. The numbers in this article, such as the number of receptors or vein pressure, come from specific studies or lecture materials. When reading original sources, check the experimental conditions, as the meaning of the numbers can change depending on the context.