Plantar fasciitis is characterised by intense pain and stiffness on the inside and underneath the sole of the foot, typically first thing in the morning when attempting to put your feet to the floor.
If suspected, it’s important to seek out diagnosis by a qualified practitioner (which doesn’t include Doctor Google!), as a full lower body bio-mechanical assessment will be necessary to establish the cause. Often this pain comes secondary to breakdown in function further up the limb – typically in the calf area, but it’s important to find out from where, and why it’s come about.
In the short-term, rest from impact activity (for example anything involving running, jumping etc) is essential to reduce further irritation of the area. Non-impact exercise can be substituted if required, for example swimming.
Ice can be helpful to calm down irritation /inflammation. Freezing a small bottle of water and rolling it under the sole of the foot, 2-3x per day, can act to both reduce inflammation and work the joints of the foot.
Wearing soft soled shoes (e.g., trainer) with cushioning or using an insole (such a sorbathane can reduce the impact and irritation.
These can be useful to reduce the inflammation but is unlikely to completely resolve the problem if there is an underlying mechanical course that’s not addressed.
Stretching through the calf muscles particularly gastrocnemius and Soleus can be helpful. Also working the around the ankle joint.
Two to three treatments of hand on therapy will typically get things moving in the right direction, particularly if used in conjunction with the above advice.
But probably the most important thing to do, is a get it diagnosed! If you can establish and treat the underlying cause, resolution will follow.