The arch of the foot is like a bridge. The two ends of this bridge are the heel and the front of the foot. The muscles in the foot are small, but they have a big job to do in supporting the arch.
The muscles on the underside of the foot tie the two ends of the bridge together. They help keep the ends from separating when force is put through the foot.
In addition to supporting the arch, the muscles inside the foot (also known as intrinsic muscles) compress the many joints of the foot. Compressing the joints allows the larger muscles of the lower leg to raise the arch.
Cause of Foot Muscle Weakness
There is no definite answer, but I suspect the biggest contributors to foot muscle weakness for me were:
- footwear and
- too much time spent walking on flat surfaces
Shoes that have rigid soles and narrow toe boxes constrain the movement of the toes. Inside of these types of shoes, the toes no longer have the ability to spread apart or grip.
It’s reasonable to think that too much time wearing shoes and not enough time spent barefoot could result in the muscles becoming weak or ineffective.
How To Strengthen Weak Arches
Looking at the anatomy of the underside of the foot we see many muscles connecting the heel to the toes. These are the muscles responsible for keeping the ends of the bridge together.
Generally, a good first step to building foot muscle strength is to spend more time barefoot. When I began working on my arches, I would look for opportunities to go barefoot on different surfaces (e.g. grass, sand) wherever it was safe to do so.
I also gradually transitioned away from shoes with a lot of support into shoes that were more flexible with wider toe boxes.
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- Shiroshita T, Fukubayashi T. Effect of the Toe Exercises on the Medial Longitudinal Arch of the Foot. Rigakuryoho Kagaku. 2012 Aug 1;27(4).