Biopsychosocial Factors and Muscle Morphology After a Resistance Exercise

The purpose of this study is to evaluate the longitudinal effects of a four-week dynamic resistance training program using the 45-degree Roman chair on pain sensitivity changes after exercise and lumbar muscle performance in individuals with chronic low back pain (LBP). This study will consist of three specific aims. Aim 1 examines changes in local exercise-induced hypoalgesia. Aim 2 will assess changes in lumbar multifidus and erector spinae thickness using ultrasound imaging before and after the intervention. Aim 3 will evaluate changes in lumbar extensor strength (handheld dynamometry (HHD)) and endurance (Biering-Sørensen test).