Subjects will receive conventional exercise program for Chronic Neck Pain in addition to breathing exercises (diaphragmatic and pursed lip breathing) for (three sessions per week for six weeks).

Patients in this arm will receive conventional physiotherapy treatment for Chronic Neck Pain in addition to doming of the diaphragm (three sessions per week for six weeks).

Diaphragmatic breathing exercise will be taught by placing the subject comfortably positioned with either therapist or the patient's hand directed over the abdominal area and instructing the subjects to focus on an outward movement of the abdominal area throughout inspiration and an inward movement of the abdominal area during expiration. (4 sets, and as each set had 4 complete breathing breaks, these exercises will be conducted for 3 days a week for 6 weeks)

Endurance of deep cervical flexors muscles will be measured by the cranio-cervical flexion test using a pressure biofeedback instrument.

During the cranio-cervical flexion test, the subject lay in the crook lying position and the pressure biofeedback instrument will be placed under the neutral cervical spine below the occiput and inflated up to 20 mmHg.

The subjects will perform this movement at 5 different pressure levels, i.e., 22, 24, 26, 28, and 30 mmHg. Each level will be supposed to be held for 10 s, and the test will be terminated if they were unable to hold the position for 10 s at any level or if the maximum level was achieved (30 mmHg).

Forced expiratory volume in the first second (FEV1) is one of ventilatory function test parameters, measured using Spirometry, Model SpirOx plus (by Meditech company-China)

The forced expiratory volume in 1 second (FEV1) is the volume of air (in liters) exhaled in the first second during forced exhalation after maximal inspiration.

Forced vital capacity (FVC) is one of pulmonary function test parameters, measured using Spirometry, Model SpirOx plus (by Meditech company-China)

Forced vital capacity (FVC) is the volume of air that can forcefully expired from the lungs following maximum inspiration, it is measured in liters.

Peak expiratory flow rate (PEFR) is the maximal flow (or speed) achieved during the maximally forced expiration initiated at full inspiration, measured in liters per second.

Peak expiratory flow rate (PEFR) as a pulmonary function, is measured using Spirometry, Model SpirOx plus (by Meditech company-China)

FEV1/FVC ratio is a calculated ratio of Forced expiratory volume in the first second (FEV1) to Forced vital capacity (FVC).

t represents the proportion of a person's vital capacity that they are able to expire in the first second of forced expiration (FEV1) to the full, forced vital capacity (FVC).