Physical activity avoidance and fear of movement (FOM) is often observed in individuals with chronic musculoskeletal pain, along with difficulties coping with pain. There is little research regarding how FOM may also relate to reduced physical strength and altered movement patterns that may perpetuate a cycle of pain, FOM, and disability. The objective of this observational study was to compare how adolescents with juvenile fibromyalgia (JFM) exhibiting high versus low FOM (Tampa Scale of Kinesiophobia-11) differed on patient-reported measures of pain, fatigue, catastrophizing and pain interference, and performance-based measures of strength, postural control, and biomechanical function. Participants were youth with JFM (N = 135, Mean