Abridged from www.feetgenius.com
The plantar fascia is a tough fibrous sheet that supports your arch and protects the internal structures of your foot from all this wear and tear. The sheet starts along the ball of your forefoot and runs along the bottom of your foot, narrowing as it goes, to end in a connection at a small area on your heel bone.
Plantar fasciitis happens when the ligaments holding the bony joints around your foot’s arch relax too much. The arch then flattens more than usual, making the foot slightly longer. The plantar fascia can’t stretch, so it tears slightly. This always happens at the heel because a lot of force is focused there on a very small area.
Plantar fasciitis pain then goes away after the damage has been done and your foot has adjusted. More tearing happens the next time you put weight on your feet after relaxing. This plantar fasciitis cycle goes on, over and over again, until you eventually seek treatment for it.
Plantar fasciitis is the most common cause of foot pain in older people, as well as athletes, soldiers, and anyone else who has to stand up for long periods of time.
The windlass mechanism is what makes barefoot walking a no-no for people with plantar fasciitis.
When you take a step with no shoes on, your big toe bends, bringing the midfoot and hindfoot down closer to the forefoot. This is fine because it relieves pressure on the plantar fascia. But then comes the next step.
As your foot takes your weight, the big toe straightens out. The relaxed plantar fascia, which has rolled up slightly, now straightens out and pulls. This can cause fasciitis when it is repeated over and over again.
The windlass mechanism is why specialists ask you to to wear shoes all day (24 hours a day, 7 days a week), except when bathing or sleeping, during the intensive phase of plantar fasciitis treatment. The best shoes for heel pain prevent the motion that stresses the plantar fascia and give that sheet of connective tissue time to rest and heal.
However, once the pain is gone, you will still need a shoe that fits well and supports your foot all the time. Shoes break down over time, losing their support and ability to absorb shocks. Even the best pair of running shoes wears out after 300 miles.
Whether you like to exercise or just have to stand on hard surfaces for most of your work day, avoid plantar fasciitis by getting new shoes before the protection provided by your old ones fails.