If your tendon pain lasts more than a few weeks, see a doctor to rule out another, potentially more serious cause of the pain, such as a stress fracture.

The researchers posit that although the extra rigidity of the tendon makes up for the lost muscle function, it causes pain once the pumps come off and the tendons have to stretch again.

Pain in the lower calf along the Achilles tendon, the cord connecting the heel to the calf muscle.