A lack of dorsiflexion range of motion is one of the biggest risk factors for developing plantar fasciitis and also a MODIFIABLE risk factor. What's that mean? It means you can incorporate this technique demonstrated by @jfitboyd into your routine NOW to (P)Rehab your movement system!
Heel cord (or gastoc-soleus) stiffness can limit the amount of DORSIFLEXION at the ankle joint. Dorsiflexion (ankle pointing upwards) is essential in the gait cycle to allow the body to move and progress over the foot. Both, individuals with over and under pronation can benefit from improving extensibility of the GSC (Gastroc-soleus complex).
OVERPRONATION: A stiff GSC will encourage a person with a very mobile (planus) foot to unlock the midfoot and pronate excessively as a compensation, placing stress on the fascia.
UNDERPRONATION: A stiff GSC in a person with a stiff (cavus) foot will also apply more tension to the fascia due to inability to absorb shock and dissipate forces.
Traditionally the calves are stretched from the standing position by leaning against a supportive wall. However, while leaning forward, the calf muscle is performing a lengthening contraction to stabilize both joints and is not fully relaxed. The best stretching position for a relaxed calf is performed in a sitting position.
ACTIVE ISOLATED STRETCHING uses gentle repetitive motion to improve the circulation of blood and nutrients, supporting the healthy repair of tissues. It not only improves tissue length but also strength in the newly acquired range.
Sit with both legs straight out in front of you. Loop the rope around the foot of your exercising leg (still straight). From your heel, move your foot back toward your ankle, using the rope for a gentle assist at the end of the movement. Placing a ball behind the leg is an added bonus to improve the tissue quality of the calf musculature. A bent knee will allow you to more specifically stretch the soleus.