Overview
School sport benefits physical, social and emotional health, providing a sense of belonging, identity and self-esteem on a weekly basis. Sport allows for the development of friendships, skills, confidence, and commitment, and reinforces good values and disciplines. However, head impacts sustained in school sports can have significant short-and long-term brain injury consequences.
The perception that rugby is the only school sport where brain injury is a risk, is both unfair and untrue. This perception has been largely fuelled due to the focus on concussion, where a head impact (head-to-head, to ground, knee, ball etc.) causes an acute brain injury with symptoms e.g. headache, nausea, balance and co-ordination. While school rugby consistently contributes to players having concussions every season, so does football, hockey, lacrosse, netball and other school games.
While schools have greater awareness of concussion symptoms, better management procedures for recording concussion, and access to medical support services, there is a significant lack of awareness of possibly the greatest threat to the brain in school sports: sub-concussions.
Sub-concussion results from an impact of lower force than required to cause a concussion. Sub-concussive impacts are 500 times more frequent than impacts which result in concussion. A sub-concussion causes damage to the brain without any signs or symptoms.
While not every school sports player will suffer a concussion, they will typically take hundreds, and even thousands of sub-concussions every season. Whilst an individual sub-concussion is asymptomatic, multiple sub-concussions can adversely affect memory, the ability to focus, learn and think, as well as behaviour. This leads to an increased risk that a pupil will underperform [1] [2].
While it is acknowledged that concussions are not good for the brain, it is less well known that the accumulated damage of sub-concussions (and not concussions) is what contributes to later-life mood and behaviour problems including Chronic Traumatic Encephalopathy (CTE). This is a progressive neurodegenerative disease that leads to early-onset dementia in a person’s 20s/30s/40s.
In every concussion and sub-concussion there are rotational forces present. These cause the brain to rotate inside the skull, which is associated with the tearing of tiny blood vessels and brain cells. Over time, this results in the break-down of the protective blood-brain barrier and the creation of damaging neuro-inflammation.
Reducing rotational forces to the brain is essential to lower the risk of neuro-inflammation. Rezon offers every player brain protection. Halos®, created by Rezon, is a protective headband which reduces rotational forces by up to 61%.
School Sport and Brain Injury
Between ages 8-12 is when peak development of the brain occurs, but the brain continues to develop through the refinement and rearrangement of brain pathways and connections until early 20s.
Axons are the tail-like structures that connect neurons in the brain and connect neurons to other cell types. Axons are coated in myelin; this improves how the electrical discharges transfer information along the axon – and is crucial to healthy brain function. Myelin is formed as the brain develops, beginning around the second trimester of gestation and a few months after birth, and continuing until the mid-20s.
Children and youths have less myelin than adults, which is problematic because myelin protects the axon. Axons with little myelin are more exposed and prone to damage from concussions and sub-concussions. Less myelinated axons also don’t recover as well from injury as highly myelinated axons.
This means a school sports player is more vulnerable to brain injury and their brains undergo noticeable changes after just one season of head impacts, even if they were never diagnosed with a concussion.
How do head impacts in school sports injure the brain?
Concussion
A player should be removed from play as soon as they are suspected of having a concussion and not return to play. ‘If in doubt, sit them out’ is the strapline of the UK-wide concussion guidance published in 2023, making clear no-one should return to sport within 24 hours of a suspected concussion.
A concussion can cause both short – or long-term physical, cognitive, social, and emotional symptoms. These changes may lead to problems with memory, communication, personality changes, and sleep disruption, as well as depression. This will affect life at home, in school and on the sports pitch.
Pupils who sustain a concussion are at increased risk of developing mental health issues such as anxiety and neurotic disorders, behavioural disorders, mood and eating disorders, schizophrenia, substance use disorder and suicidal ideation [3].
Persistent Post-Concussion Symptoms (PPCS)
While concussion symptoms will likely settle for most pupils after a short time, they may persist over two to four weeks on a gradually-diminishing basis. But changes in the brain (white matter brain connections and blood flow) can persist a year or more after a concussion [4]. So, it’s not as simple or straight-forward as following a return to play schedule with medical sign-off for the brain to heal.
Up to 1 in 3 individuals will develop Persistent Post-Concussion Symptoms (PPCS), meaning an extended recovery time with cognitive, behavioural and emotional difficulties. This can last for months to years. Although PPCS symptoms vary by individual, common symptoms include:
- Headaches
- Fatigue
- Dizziness
- Cognitive difficulties
- Emotional changes
These symptoms can significantly impact a pupil’s everyday life, and individuals with PPCS are at greater risk of experiencing depressive symptoms. The most common PPCS outcomes measured for sports concussion were depression and cognitive functioning (e.g. memory, poor concentration, slower processing, frustration, and irritability) [5].
Females experience more significant post-concussion issues and a longer period of recovery post-concussion. Post-concussion anxiety and depression are widely recognised as more prevalent in females than males by 2:1 [6].
Second Impact Syndrome (SIS)
Second Impact Syndrome (SIS) is a very serious risk when a pupil suffers a further concussive head injury before they have made a complete recovery from an initial concussion. This causes the brain to swell rapidly and catastrophically. The second injury may occur minutes, days, or weeks after an initial concussion, and even the mildest impact can lead to SIS. This is often fatal, and almost everyone who is not killed is severely disabled, especially if a full recovery from the initial concussion has not been made. This condition primarily occurs in school-age children.
“After a serious concussion from a hockey ball impact, Aaron was really apprehensive about returning to the sport he loves. Rezon Halos® helped make that return to hockey possible — for him, and for us as parents. Even if they haven’t had an injury, it’s worth wearing to prevent serious injury.”
— Andrew Brompton | Parent & Rezon Customer | ⭐⭐⭐⭐⭐
Sub-concussions
What has been ignored for too long in school sports and wider across sport is sub-concussions. These small-force impacts are 500 times more frequent than a concussion, can damage the brain and are without any symptoms, meaning players aren’t given time to recover or even aware they need to recover.
Sub-concussions impact memory, ability to focus, and brain function, and they increase the risk of pupils to underperform. Every school sports player is at risk from sub-concussions. A school sports player will experience hundreds to thousands of sub-concussions in a season.
The rotational forces present in sub-concussive impacts rotate the brain inside the skull, tearing tiny blood vessels and brain cells. This creates inflammation and the production of neurochemicals in the brain, which results in damage to the blood-brain barrier – a structure designed to protect the brain by letting in essential nutrients while keeping harmful toxins and inflammatory cells out.
When the brain is subjected to repetitive and frequent sub-concussions, the responses from the earlier sub-concussion haven’t yet returned to normal levels. So subsequent sub-concussive injuries can cause an exaggerated production of neurochemicals and an exaggerated inflammatory response. This becomes harmful to the brain, rather than protective. It damages brain tissue and leads to the irreversible death of brain cells. Over time, this leads to changes in a brain protein called tau and increases the risk of CTE.
Brain injury from the accumulated damage of sub-concussions starts in school sports! Young athletes do exhibit cellular changes in the brain associated with CTE, even in the absence of diagnosed concussions [7].
The ‘If in doubt, sit them out’ phrase and associated guidance from the UK Government Concussion Guidelines for Grassroots Sports (2023) and the Australian Government Sport Commission Concussion and Brain Health Position Statement (2024) distracts from the accumulated damage of sub-concussions. Sub-concussions fall outside the scope of the ‘If in doubt’ messaging and guidance. This leads to players, coaches, parents, and teachers believing that education around the recognition and removal of players with observable brain injury is the responsible mitigation technique, instead of trying to reduce sub-concussions in the first instance. Unintentionally, this is a potential consequence of a well-intentioned approach to public health education on concussion recognition and management, which misses the point on sub-concussions entirely.
For the majority of school sports players, cumulative asymptomatic sub-concussions are THE greater DANGER than concussions.
Rezon Halos®: Protecting Your Brain in Sport
Halos® is a groundbreaking sports headband that protects the brain. It’s the only headgear of its kind that is designed to reduce your risk of concussion and developing Chronic Traumatic Encephalopathy (CTE) from the accumulated damage of sub-concussions.
Why Halos®?
- Reduces concussion risk by 74%*
- Reduces rotational force to the brain by up to 61%, and linear force by up to 64%*
- Sleek, lightweight, flexible and hypoallergenic
- Water and tear-resistant
- Internationally recognised Virginia Tech 5 star safety rating
- The only CE/UKCA Category II PPE-certified protective headband – the UK and EU legal standard for protective headwear
*based on independent testing
As seen in
“It doesn’t matter how good your concussion management is, or if you don’t even get a concussion, it’s that large exposure to repeated impacts, many of which will be non-concussive, are still doing subtle damage to the brain that causes CTE.”
Dr. Michael Buckland, senior neuropathologist and Head of the Molecular Neuropathology Program at the Brain & Mind Centre, University of Sydney.
Concussion and sub-concussion prevention is not possible in sport, despite the proposed changes around playing technique (tackle height, limiting heading), rules, laws, technology and better aftercare. Currently, school sport is focused on the management of concussion rather than brain protection. Whilst the effects of concussion may be instantly visible, repetitive brain injury from sub-concussions over many years may not be recognised until later.
What is preventable is CTE, by lowering the damage from rotational forces in sub-concussions to the brain. Doing this from as an early age as possible, meaning it is never too early to protect the brain in school sport.
Getting the balance of being able to enjoy the many benefits of school sports with reducing the risk of concussion and damage from sub-concussions means that the focus should be on brain protection.
Rezon Halos® brain protection can reduce the risk of concussion and the accumulated damage from sub-concussion, while enabling sports participation and protecting each pupil’s future.
Brain injury risk goes beyond the obvious school sports
In football, brain injury has become overly focused around heading the ball, with limiting of heading in children under 12 and calls to ban it outright across the game. But this is more than heading. The real issue is rotational forces to the brain in concussion and sub-concussive impacts. Rotational forces occur from angled hits to the head, be it head-to-head, head-to-ball, head-to-ground impacts – all of these cause the brain to rotate inside the skull and brain cells to shear in a twist-like movement. Heading accounts for only 13% of impacts based on the study of mechanics of head impacts in football [8]. 87% of angled impacts to the head come from other sources e.g., head to head, head to knee, head to elbow, foot and hand. Focusing on heading is really missing the point on brain injury in football.
In rugby, the recent focus in schools has been on contact guidelines, revised playing techniques, lower tackle heights, and in some instances introduction of smart mouthguards (detecting head impacts). There have been calls to ban tackles, rucks, and mauls from the game and to stop schools making rugby compulsory. The focus of school rugby is still on concussion identification and management, rather than pro-active protection and addressing sub-concussions.
Rugby scrum caps/headguards are used in schools, but with little understanding of their limited functionality beyond cuts and scrapes. Headguards compliant with World Rugby regulation are not intended nor expected to protect against any form of concussion, sub-concussions or skull fractures. This explains why multiple studies [9] have illustrated that conventional headgear offers no statistically significant prevention or protection against concussion. Yet most players (82%), coaches (66%) and referees (64%) incorrectly believe protective equipment prevents concussion in rugby [10]. And parents remain unaware!
Whatever the sport, whatever the school – a pupil’s brain is vulnerable. The opinion that brain injury is only limited to certain school sports is incorrect. Any school sport that has risk of head impacts from head to head, ball, ground, knee, elbow, and falls will give rise to the risk of concussion and almost certain sub-concussions. This includes rugby, football, hockey, netball, lacrosse, tennis, cricket, gymnastics, handball and other sports.
Duty of Care
In the UK, over 1,000 former professional rugby and football (soccer) players – some of whom have been diagnosed with early-onset dementia and CTE – are taking the sport’s governing bodies to court over the lack of care and failure to protect them from the risk of brain trauma whilst playing. This now constitutes one of the biggest medicolegal cases, ever.
Increased research and dialogue around CTE risk have heightened the expectations on those with a legal duty of care. This extends to schools, school governors and sports teachers to take greater steps to preserve brain health and reduce the risk of repeated brain injury. For schools with a long history and tradition of participation in particular sports, a discussion of brain injury is an unwelcome cultural shift.
The duty of a sports teacher goes beyond that of a reasonable parent at home with responsibility for the care of the family. This “enhanced duty” arises from factors such as the low ratio of teachers to children, the school environment and equipment, and from children interacting with other children who might act unpredictably and sometimes dangerously [11].
A duty of care does not oblige a school to reduce all risks to the lowest level reasonably practicable, but it does require a measure of discretion and judgement. In the UK, an assessment of risk which guides practice and policy in different areas of a school’s sports activities is an essential element of the discharge of both a school’s statutory and common law duties of care.
Currently the focus by schools is on management of concussion, and not on sub-concussions and their long-term damage to pupils. A pupil’s concussion history is not the crucial variable in the risk and severity of CTE, sub-concussions are.
Schools rightly place safeguarding at the centre of their culture and practice. A school’s duty is to safeguard children from harm, or the risk of harm, which includes physical harm.
Where a school is providing equipment to those within its care described as ‘protective’ in the belief that it will be worn to provide any form of protection against one or more hazards, the minimum legal requirements for that protective equipment must be met. All head protection claiming to protect the wearer is Personal Protective Equipment (PPE) and is included within the scope of the Regulation (EU) 2016/425. It must carry the CE and or UKCA mark to be legally placed on the market in the UK, and the CE mark for Europe. This is regardless of any other ‘approvals’ offered by sporting bodies or standards used for testing. The PPE must be accompanied by a Declaration of Conformity, or a web address where this can be viewed.
Failure to ensure products used for protection comply with the PPE Regulation 2016/425 will not demonstrate a school’s duty of care, and could leave a school criminally liable for injuries received as a result of wearing uncertified protective equipment.
Rezon’s answer to brain injury in school sports
The brain is at risk not just to a single or high-force impact which triggers a concussion, but also to multiple sub-concussions which are invariably unnoticed and undetected in almost all school sports. Every head impact in training and playing has the potential to be life-changing.
Whilst the effects of concussive brain injury may be instantly visible, repetitive sub-concussive brain injury over many years may not be recognised until later, meaning it is never too early to protect the brain. Whether you enter professional sport or continue to play post-school, the damage of sub-concussions will already be done – it happened on the school pitch!
The most significant mitigation to reduce brain injury risk is reducing the transmission of rotational forces to the brain, which is where Rezon is focused. Halos® is uniquely and intentionally designed to reduce the transmission of rotational forces to the brain in concussive and sub-concussive impacts in school sports.
Insights
Our insights provide focused, hard-hitting, five-minute articles from Rezon, giving more informed insights regarding brain injury in school sports.
- The impact of concussion on school performance in Australian children: a population-based matched cohort study, R Lystad, A McMaugh, G Herkes, G Browne, T Badgery-Parker, C Cameron, R. Mitchell, 2022
- Impact of childhood traumatic brain injury on educational attainment in Finland from 1998 to 2018: a retrospective register-based nationwide cohort study, J Möttönen, I Kuitunen, VT Ponkilainen, VM Mattila, 2025
- Risk of Mental Health Problems in Children and Youths Following Concussion, Andrée-Anne Ledoux PhD, Richard J. Webster PhD, Anna E Clarke MSc, Deshayne B Fell PhD, Braden D Knight MSc, William Gardner PhD, Paula Cloutier MA, Clare Gray MD, Meltem Tuna PhD, Roger Zemek MD. 2022.
- Post-Concussion Brain Changes Relative to Pre-Injury White Matter and Cerebral Blood Flow, NW Churchill, MG Hutchison, SJ Graham, TA Schweizer, 2025
- Sex differences in baseline neuropsychological function and concussion symptoms of collegiate athletes, T Covassin , C B Swanik, M Sachs, Z Kendrick, P Schatz, E Zillmer, C Kaminaris. 2006.
- Suicide in women, Lakshmi Vijayakumar. 2015.
- Repeated head trauma causes neuron loss and inflammation in young athletes, Morgane LMD Butler, N Pervaiz, K Breen, S Calderazzo, P Ypsilantis, Y Wang, J Cammasola Breda, S Mazzilli, R Nicks, E Spurlock, MM Hefti, KL Fiock, BR Huber, VE Alvarez, TD Stein, JD Campbell, AC McKee, JD Cherry, 2025
- Biomechanical investigation of head impacts in football, C Withnall, N Shewchenko, R Gittens, J Dvorak, 2005.
- Rugby headgear and concussion prevention: misconceptions could increase aggressive play, Menger R, Menger A, & Nanda A, 2016.
- Concussed or Not? An Assessment of Concussion Experience and Knowledge Within Elite and Semiprofessional Rugby Union, Mathema P, Evans D, Moore IS, Ranson C, Martin R, 2016.
- Pook v Rossall School [2018] EWHC 522 (QB).
