The Impact of Eye and Body Training on the Injury Rate of Concussions in Female Soccer Players

Effects of Vestibulo-oculomotor and Neuromuscular Training on the Incidence of Concussions and Musculoskeletal Injuries in Competitive Female Football Players

The research project aims to find out how special training influences the frequency and severity of injuries among female footballers in the top Swiss league. The project also aims to help establish normative values that are specifically tailored to women. The participating clubs will be randomly assigned to a comprehensive pre-season baseline examination with training recommendations based on the performed examinations (intervention group) or control group (normal training). Over the course of the 2024/2025 season, both groups will be compared in terms of the incidence and severity of concussions and musculoskeletal injuries. Initial results will be available in spring 2025 to coincide with the start of the European Women's Football Championship.

The investigators' hypothesis is that the training recommendations in the intervention group will lead to a lower incidence of concussions and that the players will show better injury prevention as a result of these exercises.

All clubs in the top women's league in football will be contacted and asked to take part in the study. The baseline examinations will ideally take place in June and August 2024 to allow sufficient time to implement the training recommendations. The baseline examinations include a range of assessments addressing various systems potentially impacted by a concussion. These assessments encompass a standardized questionnaire, as well as vestibular, neurocognitive, balance, neck, and neurological evaluations.

Due to the availability of the players, baseline examinations may also have to take place in September. The players in the intervention group are also given specific training recommendations for the prevention of head injuries, which are compiled by experts (neurologists, sports scientists, physiotherapists and neuroscientists). The exercise selection covers several areas that can be affected after a head injury. Each section contains 8 different exercises with increasing levels of difficulty (3x Basic-3x Intermediate-2x Advanced). The recommendations should be used as a warm-up program throughout the season before each training session. The coach or athletic coach will lead the warm-up program and ensure that each player follows the sequence and completes each phase according to the scheduled weeks. The warm-up program should be conducted as an 8-week cycle.

The exercises are sent to the coaching staff in writing and by means of a video using our Neuroreha-Tool app. The coaches have access to the specific prescribed exercises. Each exercise is repeated 2-3 times and each exercise takes 50 seconds. In total, the warm-up will take 10-15 minutes.

During the football season from August 2024 to April 2025, players (both intervention and control groups) will be asked every two weeks to submit information about any injuries sustained in the match via the My REDCap app or the REDCap online survey. In the event of an injury, the date, type, and injured body region will be recorded via REDCap. Training adherence will also be documented for both groups (intervention group: number of training minutes for specific vestibulo-oculomotor and/or neuromuscular training exercises; control group: minutes of regular training).

After 8 weeks, a follow-up of the standard baseline tests will be repeated to measure the effects of the training recommendations. Each player receives a short report on the results of their examination within one week of the follow-up examination.

If a player suffers a concussion, they will be asked to complete the post-concussion symptom scale (PCSS). Players can also indicate if they wish to be contacted by the BrainCare institute for targeted diagnostics and/or therapy. On the day of the baseline examination, players will be thoroughly informed about the definition and correct recording of all endpoints collected in the follow-up. This information will also be available online on the app at any time. A recently published study confirms the usefulness and user-friendliness of a mobile app for monitoring training adherence and assessing pain using a pain rating scale.

Once a month, the club's contact person - ideally a member of the medical team who was also present at the baseline test - is contacted by the project management to verify the information and record the severity (i.e. the number of days the player is out of action) of injuries. The number of match appearances played (in hours) is determined using Power BI from the Swiss Football Association (football.ch).

Inclusion Criteria:

• Registered player for a club in the top Swiss soccer league
• No symptoms of acute head injury at the start of the study
• Sufficient language skills to understand the study information and the informed consent form and to answer questionnaires and anamnestic questions correctly.

Exclusion Criteria:

• Symptomatic chronic diseases (e.g. tumor diseases, diabetes mellitus, cardiovascular diseases) with the exception of osteoarthritis and controlled (normotensively controlled) arterial hypertension
• Pregnancy
• Diagnosis of a psychiatric disorder/disease
• Drug abuse
• For the neuropsychological test: Known learning disability/disorder