Location of Injury: Foot
Likely cause: Stabbing pain in the heel or the arch can signal plantar fasciitis, an inflammation of the band of ligaments on the bottom of the foot. The condition is caused by too much running or walking, or wearing high heels, or shoes that are too narrow.
What to avoid: Exercises that put pressure on the heels, such as running, walking, and hiking.
What you can do: Swimming and biking are good choices because they're not weight-bearing activities. You may want to wear stiff-soled sneakers while biking to support your heels.
What would make it better: For plantar fasciitis, to decrease tension on the ligaments, do gentle calf stretches (see familydoctor.org). To strengthen the foot, grab a towel with your toes and drag it toward you.