Coronary artery bypass grafting (CABG) is one of the common procedure used in coronary artery disease patients which has significant impact on cardiopulmonary and musculoskeletal systems. In the past, phase 1 rehabilitation after procedure focus on cardiopulmonary system. Lower limb rehabilitation is also important part as it influence the cardiac function. Several studies work on post-CABG patients to improve cardiopulmonary fitness but there is less number of data on calf muscles rehabilitation in post-CABG patients. So this study aims to increase the calf muscle extensibility using post-isometric relaxation technique and static stretching.

Coronary artery bypass grafting is one of the common procedure used for coronary artery disease. It has several musculoskeletal and cardiopulmonary complications. Rehabilitation in post-CABG patients accelerates the healing process. In the past, phase 1 includes cardiopulmonary rehabilitation. In the recent years, musculoskeletal rehabilitation is one of the important part after CABG. Muscle energy technique is used to increase muscle extensibility. Different studies show favourable results of static stretching in increasing length of muscles and also of muscle energy technique in increasing length and strength of muscles. There is less evidence on increasing calf muscle flexibility in post-CABG patients. So this study will investigate the technique effective for increasing calf muscle extensibility in post-CABG patients.

This study will be conduced in Armed Forces Institute of Cardiology & National Institute of Heart Diseases(AFIC & NIHD) using non-probability purposive sampling technique. Sample size has been calculated from open epi tool is 135, 45 in each group. Patients are selected according to the inclusion criteria. Patients will be guided about the risks and benefits of the study, voluntary participation and confidentiality of the data. After taking informed consent patients will be randomly assigned to the groups using sealed envelope method. Length of the calf muscles and lower limb tempertaure will be measured before and immediately after the treatment. Post-isometric relaxation technique is given to one group, static stretching to the second group and basic cardiac rehabilitation protocol to the third group.

Group 1(Experimental group): post-isometric relaxation technique using 20% of strength, contraction time of 10 second with 15 second rest period in between+ 4 repetitions. Leg slides and ankle pumps, 2 sets of 10 repetitions. Walk for 10 minutes.

Group 2(Experimental group): static stretching 15 second hold time for stretch + 5 repetitions. Ankle pumps and leg slides: 2 sets of 10 repetitions. Walk for 10 minutes.

Group 3(Control Group): Ankle pumps and leg slides: 2 sets of 10 repetitions. Walk for 10 minutes.

Psot-isometric relaxation technique: This technique will be performed by asking the patient to contract his calf muscles using 20% of the strength. Maintain the contraction for 10 second with 15 second of rest period in between each contraction in which muscle is being lengthened. A total of 4 repetitions will be performed.

Static stretching: This technique will be performed by asking the patient to perform dorsiflexion till the point of discomfort. The patient will maintain the stretch for 15 second and 5 repetitions will be performed.

Length of calf muscles and temperature of lower limb will be measured immediately after the treatment.

Inclusion criteria

• Age 35-75 years
• Both males and females
• Post-CABG patients with saphenous vein grafting
• Post-op day 4 with no post-op complications

Exclusion criteria

• Patient with DVT/Pulmonary Embolism, fever, infection at wound site
• Patient with psychosis, osteoporosis, vascular disease
• Hemodynamically unstable patients

The outcome assessor does not know that the participant receives which treatment.