The Immediate and Accumulative Effects of Ball Heading on Neurocognitive Function Within Recreational Football Players

Harrison, J ORCID: 0000-0002-5648-146X (2026) The Immediate and Accumulative Effects of Ball Heading on Neurocognitive Function Within Recreational Football Players. Doctoral thesis, Liverpool John Moores University.

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Abstract

Growing scientific and public concern regarding the potential neurological consequences of repetitive head impacts in football has intensified scrutiny surrounding purposeful heading. While the adverse effects of sport-related concussion are well established, the implications of repetitive head impacts, such as those incurred through heading the ball, remain less clearly understood. Existing research that has examined these effects on neurological outcomes have produced inconsistent findings, often constrained by methodological limitations relating to the quantification of heading exposure, ecological validity and the sensitivity of outcome measures. Accordingly, the overarching aim of this thesis was to advance the current understanding of whether, and under what conditions, exposure to heading may pose a risk to the neurological health of recreational male football players.
To address these aims, four interrelated experimental studies were conducted, each designed to progressively build upon the methodological and empirical foundations of the preceding work. Studies 1 and 2 established the methodological foundations for subsequent investigations by evaluating a neurocognitive assessment tool and developing a heading force classification framework, which were subsequently integrated within Studies 3 and 4 to examine the acute and cumulative neurocognitive implications of heading during competitive match play. Study 1 evaluated the reliability and validity of a computerised neurocognitive test (CNT) battery designed for field-based assessment of cognitive and sensorimotor performance. Findings indicated variable psychometric performance across domains, with moderate temporal stability observed for measures of motor control, processing speed, task-switching and working memory, alongside evidence supporting construct validity through the replication of established theoretical performance patterns. Study 2 developed and validated a novel video-based classification framework capable of distinguishing between higher- and lower-force headers using observable heading characteristics. Supervised machine learning models achieved moderate-to-high classification accuracy, while demonstrating strong inter- and intra-rater reliability, supporting the feasibility of scalable heading force quantification in competitive settings.
Building on these foundations, Study 3 integrated the CNT battery and heading classification framework to investigate the acute effects of heading during competitive match play. Across two complementary investigations, findings provided little evidence to support widespread neurocognitive impairment following heading exposure, with only limited and isolated associations observed under specific exposure conditions. Study 4 extended this work longitudinally by examining whether repeated heading exposure across a competitive season was associated with acute or cumulative neurocognitive changes. Here, neurocognitive performance remained largely stable over time, with no consistent evidence suggesting that recent or cumulative heading exposure resulted in measurable cognitive decline.
Collectively, the findings of the thesis fall short of supporting the presence of systematic or widespread neurocognitive impairment following heading exposure typical of recreational-level match play. Instead, the findings suggest that the intensity, frequency and temporal distribution of impacts may be insufficient to induce detectable functional disruption. Overall, this thesis contributes to the evolving evidence base surrounding football heading by advancing methodological approaches for studying heading exposure, and providing a more nuanced understanding of the conditions under which heading may, or may not, pose a meaningful neurological risk.

Item Type:	Thesis (Doctoral)
Uncontrolled Keywords:	Football; Heading; Neurocognitive Function; Repetitive Head Impacts
Subjects:	R Medicine > RC Internal medicine > RC1200 Sports Medicine G Geography. Anthropology. Recreation > GV Recreation Leisure > GV561 Sports
Divisions:	Sport and Exercise Sciences
Date of acceptance:	22 October 2026
Date Deposited:	09 Nov 2026 11:57
Last Modified:	09 Nov 2026 11:58
DOI or ID number:	10.24377/LJMU.t.00029836
Supervisors:	Roberts, J, Bennett, S, Robinson, M and Bruno, D
URI:	https://researchonline.ljmu.ac.uk/id/eprint/29836

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