Plantar Fasciitis is the most common of injuries in people who run and jump. Court sports persons and runners in general suffer from this condition which is an inflammation of the connective tissue that covers the underside of the foot.  The condition is usually diagnosed by intense pain upon placing your foot down on the floor when you first wake up in the morning.  Slight limping until the fascia warms up and becomes malleable is a certain indicator and it can leave you unable to walk for a brief time in the morning hours.  Continuing to ignore this condition can result in a tear which will leave you unable to place any weight on the foot without intense pain.