The plantar fascia explained
The plantar fascia is the thick tissue connective tissue (plantar aponeurosis) which supports the arch of the bottom of the foot. It connects the heel bone to the toes forward to the heads of the metatarsal bones to create the arch of the foot.
There is an indirect relationship whereby if the toes are dorsiflexed, the plantar fascia tightens via the windlass mechanism. If a tensile force is then generated in the Achilles tendon it will increase tensile strain in the plantar fascia.