Achilles Tendonitis is now more accurately known as achilles tendinopathy. This is because it is not thought to be an inflammatory condition and is more likely to be due to the degeneration of the tendon. Symptoms include a gradual onset of pain, stiffness and aching of the tendon and a thickened often reddened appearance. The tendon is usually tender to touch and may contain lumps known as nodules. Initially any pain on exercise may fade as you continue and the tendon warms up. Without treatment pain will become constant and in order to.