Plantar Fasciitis involves pain on the plantar on the sole of one's foot between the heel and forefoot. It is common in runners. What causes runners to get plantar fasciitis? My theory (from first hand experience in the fall of 2008) is wearing shoes with significant support weakens and atrophies the muscles in the foot which are then unable to handle faster paces or long runs without tearing. In my opinion the best way to recover and prevent the dreaded PF is to run barefoot. Even 10% of your weekly mileage barefoot goes a very long way toward not getting the injury.
0. Run barefoot. Even walking around barefoot helps strengthen your feet. Wearing Vibram Five Fingers counts as barefoot although a little time without anything on your feet is even better. It doesn't have to be fast or far either even a few minutes will strengthen your feet.
1. Toe Curls. Curl up a newspaper or towel that you are standing on, or several newspapers or towels. See the video below for an example. How many times should you do it in one session and how frequently should you do a session? Start with one set of 2-3 feet worth of curled material per day and progress to two sets of 5-6 feet of material per day over about two weeks. Once you are healed 2-3 feet of material curled 2-3 times per week with likely keep your feet strong.
2. Shin Ups or Toe Raises. Leaning up against a wall with your feet about a foot away from the wall about shoulder width apart slowly raise and lower your toes 30 times without ever completely lowering your feet to the ground then without stopping do 30 fast toe raises and during this part your shins will start to burn, because your shins are weak. Runners get shin splints because they are running on hard surfaces strengthening their calves with every step and not strengthening their shins. The muscle imbalance is an injury waiting to happen. This is the best cure for shin splints I have encountered in 21,000 miles over 11 years. If it doesn't work, you might not have shin splints. See the video below for an example.
3. Pianos. I might have actually created this one. The others I learned about from coaches or one of the running specific websites. This is a great plantar fasciitis exercise because it causes the muscles in your feet to pull against each other breaking some of the unwanted connections that happen between muscle fibers and contribute to knots. At least, that's my interpretation of why it works based on my experience with muscle knots. All you need to do is stand up without leaning on anything and press your big toes down and lift your four outer toes up, then press your four outer toes down and lift your big toes up. Continue to go back and forth between the two positions until you can't any more. It takes practice when you start and the focus should be on getting the toes extended not any specific number of repetitions. See the video below for an example.
Disclaimer: I am not a doctor. I am a Master of Science, but in Materials Science and Engineering. These exercises have not been approved by a doctor or medical board, but how many doctors run half as much as I run or work with patients that run half as much as I run? In summary, you could die doing these exercises don't blame me for it.