Deep Neck Flexor Exercises Versus Myofascial Release of Suboccipital Muscles in Chronic Tension-type Headache

Inclusion Criteria: 1. Age between 18 and 55 years; 2. based on ICHD-3, Headache that occurs 15 days per month and lasts on average for \>3 months (180 days per year), lasting hours to days, or unremitting, and has at least two of the following four characteristics recognized as CTTH: bilateral location, pressing or tightening (non-pulsating) quality, mild or moderate intensity, not aggravated by routine physical activity such as walking or climbing stairs and both of the following: no more than one of photophobia, phonophobia or mild nausea, neither moderate or severe nausea nor vomiting; 3. Dosage and type of prophylactic medication have not changed in the months before the beginning of the trial; 4. The participant does not intend to change the dosage and type of prophylactic medication during the study; 5. CVA less than 49 degrees, 6. Participants have the ability to understand and read Persian to complete the questionnaire. Exclusion Criteria: 1. Participants with infrequent ETTH, or other primary or secondary types of headache; 2. Pain aggravated by movement of the head; 3. Severe pain or significant decrease in ROM of the cervical spine; 4. Previous trauma to the cervical spine; 5. History of injection, surgery, severe disc protrusion, or neck or shoulder fracture that affects treatment; 6. Metabolic or Neurological disorders such as Bow hunter's syndrome or epilepsy; 7. Taking more than 200 pieces of morphine or other strong analgesics per month; 8. Physiotherapy treatment for headache within 6 months before starting treatment; 9. Joint stiffness, atherosclerosis, or advanced osteoarthritis; 10. Manual contraindication includes: (a)The participant has substance or alcohol abuse; (b)For whatever reason, the participant does not want to be touched by the therapist; (c)Symptoms are severe and irritating; (d)Underlying diseases (such as rheumatoid arthritis) or metabolic disorders (such as osteoporosis or soft tissue laxity of the treatment area); 11. Pregnancy; 12. Spielberger State-Trait Anxiety Inventory (STAI) scores more than 85; 13. Absence of two consecutive sessions and more than treatment sessions.