The Achilles tendon is a group of tissues connecting the calf muscles and heel bone. When intact, this tendon facilitates the mechanics of walking and movement in the foot, ankle and calf. The American College of Foot and Ankle Surgeons explains that a variety of causes contribute to Achilles pain and swelling, typically with overuse of this tendon being a primary factor. Simple treatments, including icing the injury and medication, often promote healing after injury; however, in severe cases, surgery may be necessary to repair damage.

Low Arches and Footwear

The foot and the heel work together to facilitate movement such as walking or running. People with flat feet, or low arches in the foot, are more prone to developing pain and swelling of the Achilles tendon due to the muscles of the heel working harder. The arch of the foot decreases the resistance caused during flexion and extension of the foot during movement. The lower the arch, the more demand placed on the adjoining muscles.

The American Academy of Orthopaedic Surgeons explains that shoe and arch support can make a difference in frequency of pain experienced due to flat feet. In addition to shoe cushioning, people with flat feet may also benefit from utilizing simple stretching exercises prior to extensive walking to warm up the muscles of the heel area.

Over-Exertion and Stress

Athletes commonly experience Achilles tendon problems due to overuse of the lower extremities. MedlinePlus notes that engaging in sports such as basketball, which requires sudden starts, stops and jumps, may increase your risk for developing Achilles tendinitis. Adding different exercises to workout routines that involve climbing or increasing running distance also contributes to increased swelling and pain. Prior to starting exercise, warming up the muscles through stretching and flexing the calves, legs and heels aids in preventing potential swelling after over-extending the Achilles muscles. During exercise, if the heel area makes a crackling sound, or feels weakened or stiff, this is an indication of injury which will become painful and cause inflammation.

Bursitis

The American Academy of Family Physicians explains that with the Achilles tendon being the largest and most-used tendon of the body, it is vulnerable to injury over time due to the natural aging process. A condition called bursitis commonly occurs in the elderly causing pain and swelling because of overuse of weakened muscles and bone spurs. The condition tends to subside in resting positions; however, upon initiation of physical activity, pain increases. Aging heel tissues can prevent normal walking and make wearing shoes difficult due to inflammation around the ankles and feet. Icing the area, stretching and anti-inflammatory medications may offer some relief to this cause of Achilles tendon pain. The condition tends to persist in older adults, however.