This study aims to compare the effects of post-isometric relaxation (PIR) and post isometric stretching (PIS) techniques on reducing neck pain, improving range of motion, and decreasing neck disability in individuals with neck pain. A randomized controlled trial will be conducted with 50 participants, who will be randomly assigned to one of two groups: one receiving PIR and the other receiving PIS. A single-blind method will be used, meaning the participants will not know which group they belong to. Participants will be selected based on specific criteria related to neck pain and will then be randomly allocated to the PIR or PIS group. Initially, all participants will receive two standard treatments: Transcutaneous Electrical Nerve Stimulation (TENS) and hot pack application. After these treatments, one group will undergo post-isometric relaxation (PIR), which involves 3-5 repetitions of muscle contraction and relaxation, conducted over five consecutive sessions. The other group will receive post-isometric stretching (PIS), which involves stretching after muscle contraction and relaxation, also administered over five consecutive sessions. At the end of the intervention, pain, range of motion, and neck disability will be measured. Pain will be assessed using a standardised pain scale, range of motion will be measured with a goniometer or other appropriate tools, and neck disability will be evaluated using the Neck Disability Index (NDI). Statistical analysis will be performed to compare the effectiveness of PIR and PIS in terms of pain reduction, range of motion improvement, and decreased neck disability.

Neck pain is one of the most prevalent musculoskeletal complaints among young adults, with studies reporting a prevalence of up to 75.7%, making it the fourth leading cause of disability worldwide. Research suggests that weak cervical musculature, reduced muscle-to-bodyweight ratios, and imbalances in muscle strength are key contributors to neck pain and associated disability. Muscle Energy Techniques (METs), particularly Post-Isometric Relaxation (PIR) and Post-Isometric Stretching (PIS), have been widely used to address these issues. PIR involves gentle isometric contractions followed by muscle relaxation and is effective for managing active muscle tone, making it suitable for acute conditions. However, it lacks a stretching component to target passive tone. PIS adds a post-contraction stretch, potentially addressing both active and passive tone, but may cause discomfort in sensitive individuals. While both techniques have shown positive outcomes in reducing pain and improving function, limited research directly compares their effectiveness. Therefore, this study aims to compare PIR and PIS in terms of pain relief, cervical range of motion, and functional improvement in individuals with mechanical neck pain.

According to M.Osama et al in 2020 a study was conducted to compared autogenic inhibition (AI) and reciprocal inhibition (RI) muscle energy techniques (MET) to static stretching (SS) for managing mechanical neck pain. Both AI-MET and RI-MET outperformed SS in enhancing isometric strength, with no adverse effects observed. The findings highlight AI-MET's superiority and support its use in neck pain rehabilitation.

Another study was conducted by Osama M 2024, 78 participants a randomized trial concluded that Muscle and Movement specific PIR is effective in improving neck pain, disability and ROM. Dudonienė V et al preformed a study in 2024 that aimed to investigate the 3 effectiveness of post-isometric relaxation (PIR) compared to self-stretching (SS) in working-age individuals with chronic non-specific neck pain. Result showed PIR group achieved lower pain intensity, greater neck extension ROM and lower neck disability index compared to the SS group.

A study conducted in 2022 investigates the effects of post-isometric relaxation (PIR) versus myofascial release therapy on non-specific neck pain management. Results showed that the PIR group had significant improvements in pain (measured by VAS), disability (NDI), cervical extension, and social QoL compared to the MFR group.

Another study investigated the effectiveness of post isometric relaxation (PIR) combined with traditional physical therapy for treating chronic mechanical neck pain compared to traditional therapy alone. Results showed significant reductions in pain and increases in cervical range of motion (ROM) for group adding PIR to conventional therapy.

The study compares the effectiveness of post-isometric relaxation (PIR) and passive neck retraction mobilization (PNRM) in treating nonspecific neck pain. This study suggests that PIR to be a more effective treatment option for nonspecific neck discomfort.

Inclusion Criteria: • Age ranging from 19-44 years old

• Both gender
• With sub-acute or chronic neck pain for at least 4 to 12 weeks
• Pain intensity on NPRS ranging 4-8
• Limitation on neck movement

Exclusion Criteria:

• • Positive history of fracture

  • Surgery in the cervical region
  • Any sort of physical trauma in the cervical region in the last 12 months
  • Thoracic Outlet syndrome
  • Cervical radiculopathy
  • Cervical myelopathy
  • Cervical spondylosis
  • Cervical syringomyelia
  • Any systemic disorder including malignancy or inflammatory and rheumatic disorders
  • Infection
  • Vascular syndromes such as vertebrobasilar insufficiency (VBI).