Achilles tendinopathy is relatively common. The etiology and pathogenesis are unknown. It was thought to include an inflammatory component, but recent research using microdialysis technique and gene technology has shown no chemical inflammation in chronic midportion Achilles tendinosis. The neurotransmitter glutamate and its NMDAR1 receptor were found in tendons using microdialysis and immunohistochemical techniques, with concentrations of glutamate significantly higher in tendons with tendinosis than in normal tendons. Treatment of Achilles tendinopathy is difficult, and chronic cases often require surgery. Recent research, however, has shown promising results using nonsurgical methods. Painful eccentric calf muscle training has shown good short-term results. Also, in a recent study, sclerosing of neovessels in the area with pain and tendon changes showed promising short-term results.