One of the most common injuries in tennis and jogging, is plantar fascitis, pain on the bottom of the heel. A band of tissue called the plantar fascia starts on your five toes, extends backward along the bottom of your foot and attaches on the bottom of your heel. When you run, you land on your heels and then raise yourself on your toes as you shift your weight to your other foot. At that point, all your weight is on your plantar fascia. When the force on the fascia is greater than it's inherent strength, it tears at its weakest point at the heel.
Doctors have no medications that help heal the plantar fascia.
Cortisone injections and aspirin-like pills can reduce pain, but they also delay healing. If you have plantar fascitis, stop running until you can run without feeling pain. Since you pedal with your knees and hips and place little force on your fascia, you can usually pedal a bicycle without feeling pain. Use shoes that have flexible soles. Wear arch supports that limit the rolling in motion of your feet, and stretch your calf muscles.