Core Muscles are described to provide proximal stability for distal mobility. Two types of muscle fibers comprise the core muscles: slow-twitch and fast-twitch.

The core acts through the thoracolumbar fascia, ‘‘nature’s back belt.’’ The transversus abdominis has large attachments to the middle and posterior layers of the thoracolumbar fascia (Bogduk,1997). Additionally, the deep lamina of the posterior layer attaches to the lumbar spinous processes. In essence, the thoracolumbar fascia serves as part of a ‘‘hoop’’ around the trunk (McGill,2002) that provides a connection between the lower limb and the upper limb (Vleeming et al,1995). With the contraction of the muscular contents, the thoracolumbar fascia also functions as a proprioceptor, providing feedback about trunk positioning.

The intertransversariimediales, interspinales, and rotatores are extremely close to the centre of rotation of the spinal segments. Their very small physiological cross-sectional area and their high density of muscle spindles (4.5-7.3 times richer than the number in the multifidus) suggests that they may act primarily as position transducers of the spinal column .This would suggest that these LSS Muscles would appear to be particularly important to the coordination required in Core Stability (Wendell et al,1995).

A randomized controlled trial Rosa Cabanas-Valdés et al (2007) on Core stability exercises in addition to conventional therapy improved trunk control, dynamic sitting balance, standing balance, gait and activities of daily living in sub-acute post-stroke patients. Also, additional trunk exercises (Van Criekingeet al 2017) showed the effectiveness of on gait performance in subacute stroke. However the duration of onset in their experimental group was 25.12 (17.30) days a time when recovery can be attributed partly to natural and therapeutic reasons. Following intervention, Eun-Jung Chung et al (2013) reported in chronic stroke the core exercise group showed a significant change in TUG, velocity, and cadence. XiboSun, et al (2016) reported that Core stability exercises have a better effect on patients with hemiplegia than conventional exercises.

Review of literature on effect of core muscle strengthening on the trunk proprioception and functional mobility in chronic stroke is meagre. Hence this study focuses on evaluating the therapeutic effect of core muscle strengthening exercises in addition to the conventional trunk physiotherapy program on trunk proprioception and functional mobility in persons with chronic stroke.