Objectives To determine the effect of heading a soccer ball on serum neurofilament light (NF-L) protein, plasma tau protein and symptom metrics including total number of symptoms reported and symptom severity scores on the Standardized Concussion Assessment Tool— 3rd edition (SCAT3).
Methods Eleven male collegiate soccer players were recruited to take part in three experimental conditions including heading, sham and control conditions. Participants were required to perform 40 headers in 20 min in the heading condition, and control 40 soccer balls directed at them with their hands, chest or thigh in the sham condition. No ball contact was made during the control condition. Blood sampling and SCAT3 symptom assessments were completed prior to and 1 hour following conditions. A subset of participants returned 3 weeks following the heading condition for blood sampling.
Results NF-L was elevated at 1 hour (p=0.004) and 1 month (p=0.04) following the heading condition, and at 1 hour (p=0.02) following the control condition. Tau levels remained unchanged following all conditions. The total number of symptoms (TS) and symptom severity (SS) scores from the SCAT3 were both elevated following the heading condition (p=0.01 and p=0.03, respectively). Both TS and SS decreased following sham (p=0.04 and p=0.04) and control conditions (p=0.04 and p=0.04).
Conclusion An acute bout of soccer heading is associated with increased NF-L concentrations at 1 hour and 1 month following the session and can lead to symptoms commonly reported following sport-related concussion.
This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.
Contributors CW, JDS, KeB, JB, JD, ADW and PvD all contributed to the conception of the study and data collection. CW, HZ, KaB and PvD contributed to data analysis and interpretation, drafting and revision of the manuscript, and final approval of the version submitted for publication was approved by all authors.
Funding This research was funded by grants to PvD from the Canadian Institutes for Health Research (CIHR), Canada Foundation for Innovation (CFI) and Mitacs. CW was supported by the Mitacs Accelerate Programme.
Competing interests HZ and KaB are co-founders of Brain Biomarker Solutions in Gothenburg AB, a GU Venture-based platform company at the University of Gothenburg. HZ has served at advisory boards for Eli Lilly and Roche Diagnostics and has received travel support from Teva. KaB has served as a consultant or at advisory boards for Alzheon, BioArctic, Biogen, Eli Lilly, Fujirebio Europe, IBL International, Merck, Novartis, Pfizer and Roche Diagnostics.
Patient consent Obtained.
Ethics approval All procedures in this study were approved by the Clinical Research Ethics Board at the University of British Columbia and were conducted according to the declaration of Helsinki guidelines.
Provenance and peer review Not commissioned; internally peer reviewed.
Data sharing statement The data will be made available upon request.