Related Experiment Video
Updated: Apr 30, 2026
In Vivo Protocol of Controlled Subconcussive Head Impacts for the Validation of Field Study Data
Published on: April 18, 2019
Rates of physical contacts, headers, ball flight occurrences, and suspected concussions in Canadian adolescent
Kenzie B Friesen1, Matthew G Neill2, Tuija A Hyyrynen3
1Sport Injury Prevention Research Center, Faculty of Kinesiology, University of Calgary, Canada; Human Performance Lab, Faculty of Kinesiology, University of Calgary, Canada.
Objectives:
To examine physical contact, head contact, header, and ball flight rates, video-suspected concussion and musculoskeletal injury between match structures (indoor and outdoor), across age (U15 and U17 players) groups and sexes (males and females).
Design:
Cross-sectional research design using video-analysis methodology.
Methods:
Youth soccer players (aged 13-18) competed in the 2022-2023 indoor (N = 10 matches) and outdoor (N = 10 matches) seasons. Sex (male vs. female), age (U15 vs. U17), and structure (9v9 vs. 11v11) were considered. Physical contacts (player-to-player), headers (head contact with the ball), ball flight occurrences, and video-suspected concussion and musculoskeletal injuries were coded via video-analysis in 20 adolescent soccer matches.
Results:
Overall, 5547 total physical contacts and 874 headers (362M; 512F) were coded. Average marginal effects demonstrated higher header rates for males (incidence rate ratio = 1.52, 95 % confidence interval: 1.32-1.76) and 9v9 (incidence rate ratio = 1.78, 95 % confidence interval: 1.53-2.06) compared to females and 11v11. Mean marginal effects also demonstrated a lower rate of physical contacts for males (incidence rate ratio = 0.95, 95 % confidence interval: 0.90-1.00) compared to females and a higher rate of physical contacts in 9v9 (incidence rate ratio = 1.68, 95 % confidence interval: 1.59-1.78) compared to 11v11. Rates of ball flight occurrence were higher for males (incidence rate ratio = 1.54, 95 % confidence interval: 1.34-1.78), indoor play (incidence rate ratio = 1.41, 95 % confidence interval: 1.59-1.78), and at U17 (incidence rate ratio = 1.43, 95 % confidence interval: 1.23-1.64), compared to females, outdoor, and U15, respectively. Female matches were associated with a higher rate of video-suspected musculoskeletal injury (incidence rate ratio = 1.94, 95 % confidence interval: 1.11-3.39) compared to males (total MSK: 35M, 19F). There were 9 suspected sport-related concussions (5M; 4F).
Conclusions:
Future research attempting to quantify or alter header exposure in adolescent soccer should consider the influence of match structure, age group, and sex of players.
