Project Summary/Abstract Gymnastics is a leading cause of head injury among sports- and recreation-related activities and is the second most common cause of emergency room visits for non-fatal traumatic brain injury among non-contact sports. As a sport, gymnastics is composed of six disciplines that utilize various skills to showcase balance, power, and artistry. The physical demands of the sport often lead to a variety of injuries, including concussion. Concussions in gymnastics commonly occur from falls and missed landings, but gymnasts are also exposed to direct (contact) and inertial (non-contact) accelerations of the head while performing complex skills that are generally not associated with concussion but may affect recovery following concussion. Additionally, athletes may experience impairments to memory, concentration, and vestibular/ocular-motor symptoms following concussion, but effects from repetitive rotational head movements, such as those experienced by gymnasts, are not well-understood. With ~ 5 million Americans participating in gymnastics-related activities, there is a critical need to understand the head accelerations experienced by gymnasts and their relationship to concussion-related clinical outcomes to inform safety recommendations, including post-concussion return to play protocols, in the sport. The objective of this study is to characterize kinematics (i.e., accelerations, velocity) of the head across skills performed in artistic gymnastics and their relationship to concussion-related clinical outcomes and evaluate the effect of safety modifications on reducing kinematic loads experienced by gymnasts. In Aim 1, 16 beginner-level (8 male, 8 female) and 16 advanced-level (8 male, 8 female) artistic gymnasts (ages 11-15) will be fitted with mouthpiece- based head motion sensors. Biomechanical data will be collected and quantified during all practices to determine the frequency, magnitude, and duration of head accelerations experienced during normal participation of the sport. In Aim 2, we will engage stakeholders in the gymnastics and sports medicine communities to identify and evaluate skill-specific safety modifications to reduce head kinematics in gymnastics. Enrolled gymnasts will complete a series of skills with two progressive safety modifications; the effect of safety modifications on reducing head accelerations will be evaluated. In Aim 3, the relationship between exposure to head accelerations during normal participation of gymnastics and concussion-related clinical outcomes will be evaluated. Changes in pre- to post-study cognition and postural control and acute changes in concussion-related symptoms will be monitored using validated clinical assessment tools and evaluated with respect to head acceleration measuring during the study. This R21 exploratory/developmental research study seeks to ultimately change the paradigm of concussion safety in gymnastics and will result in key data to support a large-scale study to develop and evaluate a biomechanically-informed return to play protocol for gymnastics. This approach will provide a framework that may be expanded to other disciplines of gymnastics and acrobatic sports to improve the safety of over 5 million athletes participating in acrobatic activities.

Project Narrative Gymnastics is a sport with unique physical demands leading to a high rate of injuries, including injuries to the head. Existing protocols that reintegrate athletes back into sport following a concussion use a graded approach, but do not fully address the multifaceted loading environment, including direct (contact) and inertial (non-contact) head accelerations experienced by gymnasts while performing complex skills. The proposed study will break ground in an understudied area of concussion research and seek to transform safety protocols in gymnastics by characterizing head accelerations and their relationship to concussion-related clinical outcomes among gymnasts and evaluating the effect of safety modifications on reducing head accelerations experienced by gymnasts.