Plantar fasciitis typically causes a stabbing pain in the bottom of your foot near the heel. The pain is usually the worst with the first few steps after awakening, although it can also be triggered by long periods of standing or rising from sitting. The pain is usually worse after exercise, not during it.

Under normal circumstances, your plantar fascia acts like a shock-absorbing bowstring, supporting the arch in your foot. If tension and stress on that bowstring become too great, small tears can arise in the fascia. Repetitive stretching and tearing can cause the fascia to become irritated or inflamed, though in many cases of plantar fasciitis, the cause isn't clear.

Though plantar fasciitis can arise without an obvious cause, factors that can increase your risk of developing plantar fasciitis include:

• Age. Plantar fasciitis is most common between the ages of 40 and 60.
• Certain types of exercise. Activities that place a lot of stress on your heel and attached tissue — such as long-distance running, ballistic jumping activities, ballet dancing and aerobic dance — can contribute to an earlier onset of plantar fasciitis.
• Foot mechanics. Being flat-footed, having a high arch or even having an abnormal pattern of walking can affect the way weight is distributed when you're standing and put added stress on the plantar fascia.
• Obesity. Excess pounds put extra stress on your plantar fascia.
• Occupations that keep you on your feet. Factory workers, teachers and others who spend most of their work hours walking or standing on hard surfaces can damage their plantar fascia.

Ignoring plantar fasciitis may result in chronic heel pain that hinders your regular activities. Changing the way you walk to minimize plantar fasciitis pain might lead to foot, knee, hip or back problems.