If the achilles tendon is affected by overuse, and then rest may be the best solution.
Frequently, though, the biomechanics of the foot are to blame. When the arch of the foot is lost, so is the spring in the foot when walking or running.
There is a ligament in the foot called the "Spring Ligament" and it's action is to work in recoil to loads that are applied when walking or running. When the arch is lost, the spring ligament can't work.
Muscles, such as the tibialis posterior have to take on the job of the spring ligament, and become overused.
Theses muscles then develop trigger points and refer pain such as this.
Treatment of these trigger points and having orthotics fitted will often solve this problem.