Cerebral palsy(CP) is non-progressive disorder, undergo mishap to the developing brain and it affect a person's ability to move and maintain balance and posture. Old name of CP is "Little's disease". Cerebral means having to do with the brain. Palsy means weakness or problems with using the muscles. In Spastic diplegic, muscle stiffness is mainly in the legs, with the arms less affected or not affected at all. The most common cause of spastic diplegia is Periventricular leukomalacia, more commonly known as neonatal asphyxia or infant hypoxia-a sudden in-womb shortage of oxygen-delivery through the umbilical cord. Strength exercise is any activity that makes your muscles work harder than usual.

The significance of this study is that it will define whether loaded or unloaded sit to stand strengthening exercises have good effect on muscle strength and energy expenditure in diaplegic CP. This will be a randomized clinical trial, data will be collected from District Head Quarter DHQ hafizabad. Study will be conducted on 32 patients. Inclusion criteria of this study is spastic diplegic CP children with age between 6 to 12 years, with GMFCS level 1 and 2 and those who are able to stand up from chair independently and maintain standing for more than 5 seconds without falling will be included.Diplegic CP children who had not received any strengthening exercise program in past 3 months and those less than 20 degrees limitation in passive range of motion in hip flexion will be included. Those diplegic spastic CP who have orthopedic intervention such as selective dorsal rhizotomy or botolinum toxin injection to lower extremities within past six months and orthopedic conditions or medical problems that prevented children from participating in exercises will be excluded. Group A will be provided with loaded sit to stand strengthening exercises. 1 repetition maximum(1-RM) will be used as loaded sit to stand test. Group B will be provided with unloaded sit to stand strengthening exercises. Pre and post session lower limb functional strength will be measured by performing functional strength tests while lower limb muscular strength will be measured via modified sphygmomanometer and physiological cost index will be measured to rule out energy expenditure.

Inclusion Criteria:

• Spastic diplegic cerebral palsy
• Age between 6 to 12 years
• Children with GMFCS level I and II
• Able to stand up from chair independently and maintain standing for more than 5 second without falling.
• Had not received any strengthening exercise program in past 3 months
• Parental commitment to allow participation without altering current activity

Exclusion Criteria:

• Participants with epileptic history and lower limb contractures are excluded
• Those who are unable to follow verbal command
• Have orthopedic intervention such as selective dorsal rhizotomy or botolinum toxin injection to lower extremities within past 6 months
• Orthopedic condition or medical problems that prevent children from participating in exercise