Hamstring Stretching Effective on Nonspecific Low Back Pain

During the Passive Knee Extension Test, participants will be positioned supine with the hip of the tested limb flexed to 90° while the contralateral limb will be stabilized. The examiner gradually extended the knee until resistance or discomfort will reported. The knee extension angle will be measured using a digital goniometer and recorded in degrees.

fingertip-to-floor (FTF) test, participants stood on a 20-cm step and will instructed to bend forward and reach toward the floor without flexing their knees. The distance between the third fingertip and the floor will measured using a tape measure and recorded in centimeters. The minimal detectable change (MDC) for the FTF test is reported as 4.5 cm

Sit- and-reach test (SRT) participants sİt with their knees fully extended and feet position against the testing box. They are instructed to reach forward as far as possible while keeping their knees extended. The furthest distance reached will recorded in centimeters

Functional Rating Index (FDI) was obtained by combining similar structures of the neck disability index and the Osweestry low back pain disability index, and its validity and reliability have been proven. The validity and reliability of the Turkish version of this survey was conducted by Bayar et al. in 2004. FDI consists of 10 parts that measure the function of the spinal musculoskeletal (waist, neck pain) system and pain. Eight address activities of daily living that may be affected by the spinal condition. Two of them address 2 different characteristics of pain. Using a 5-choice scale for each item, the amount of current pain or perceived ability to function is ranked by selecting 5 response points. 0=no pain or full function, 1=mild pain or mild limitation, 2=moderate pain or moderate limitation, 3=severe pain or severe limitation, 4=worst pain or inability to function. Scoring varies between 0-40, and as the score increases, functional status worsens

Functional disability will be assessed using the Oswestry Disability Index (ODI). The ODI consists of 10 items evaluating pain intensity and disability during daily activities. Each item will be scored from 0 to 5, with higher scores indicating greater disability. The Turkish version of the ODI has demonstrated acceptable validity and reliability (Yakut et al., 2004). ODI scores will be categorized as minimal (0-20), moderate (21-40), severe (41-60), crippled (61-80), and bed-bound (81-100) disability. A 30% improvement from baseline will be considered the threshold for clinically meaningful improvement in individuals with low back pain.

Pain status Patients pain status were evaluated with VAS between 0 and 10 for low back pain during movement. (No pain at 0 points, severe pain at 10 points)

Vertical jump performance will be assessed using the squat jump (SJ) test. Participants will start from a semi-squat position without preparatory countermovement and will be instructed to jump as high as possible. Jump height will be measured using a Vertec system, which has demonstrated acceptable validity and reliability for vertical jump assessment. Three trials will be performed under standardized conditions, and the highest value will be recorded. Jump height will be calculated as the difference between standing reach height and maximal jump reach height and will be recorded in centimeters.