The relationship between performance in core exercises and performance ability in ski jumping : a cross-sectional study of competitive ski jumpers

Background: The concept of core stability and balance are emphasized during athletic training for Norwegian ski jumpers. The impression of how important it can be for sport performance has long been a matter of interest within research. The purpose of this study was to examine the association between core stability, balance and ski-jumping performance ability in competitive ski jumpers. Methods: Eleven male ski jumpers were tested for steadiness in two commonly used core exercises (plank and balance exercise) in the ski jump environment. Ski-jumping performance ability was ranked by a group of experienced trainers. Inertial measurement units were used to obtain acceleration and angular velocity, and Oqus cameras and Qualisys Track Manager software were used to determine segment- and joint angles. Performance from the core exercises was compared to ski-jumping performance ability. Results: The main findings show a negative relationship for the steadiness in the lower back (plank exercise), and a positive relationship for elbow angle movement (balance exercise) with ski-jumping performance ability. Discussion and conclusion: Small amplitude motion in the lower back during the plank exercise is related to ski-jumping performance ability. The participants had some technical differences in execution, which may have had an impact on the results