How can you reduce concussion risk in sport?

Protection Needs to Come Before Injury

When people ask how to reduce concussion risk in sport, the conversation often goes straight to concussion protocols. That is understandable, because protocols matter. They help identify suspected concussion, remove players from play, guide medical assessment, support and track a safer return to sport/play. But concussion protocols and “sit them out” policies are not the same as brain protection in sport. These protocols only start after the brain has been damaged ^{[1, 2]}.

A pragmatic protection strategy has to begin earlier. It has to question what biomechanical mechanisms cause brain injury in sport, which exposures can be reduced without changing the sports we love, and what can lower the rotational forces transmitted to the brain when head impacts occur. That includes not only diagnosed concussion, but also repeated and highly frequent smaller-force sub-concussive head impacts, which do not cause symptoms, but still contribute to cumulative brain damage over time. ^{[1, 6, 7]}.

Watch: How can concussion risk be reduced in sport?

What actually increases brain injury risk?

Brain injury risk increases through a combination of head impact exposure, collision mechanics, and the number of years receiving head impacts. In practical terms, that includes head-to-head contact, head-to-ground contact, player-to-player collisions, awkward aerial challenges, poorly controlled contact drills, heading drills, and repeated sub-concussive impacts in both training and matches ^[6]. Brain injury risk starts from the point of first playing in childhood, it is not risk limited to adulthood or level of sport.

From a biomechanical perspective, rotational acceleration matters because it causes the brain to rotate within the skull. This is associated with tearing of tiny blood vessels and brain cells resulting, over time, in the breakdown of the protective blood-brain barrier and the creation of damaging neuro-inflammation.

Conventional padded headgear is often designed primarily for protection around cuts and abrasions. Brain protection addresses the transmission of rotational forces, the primary driver of brain injury in sport. If the aim is to reduce concussion risk, instead the more relevant issue is whether a product reduces the rotational forces associated with brain injury in concussive and sub-concussive impacts ^[4].

Does concussion protocol prevent concussion?

No. Concussion protocol comes into effect after a brain injury has already been inflicted.

What it does do is create a system for recognition, removal, assessment, recovery, and graduated return to play. Current guidance varies by sport but all recommend that players return to sport only with healthcare approval and through a stepped progression of increased activity. World Rugby’s concussion framework supports immediate recognition and removal and, in elite settings, structured HIA processes are followed where diagnosis is not immediately obvious ^{[2, 3, 5]}.

That is essential for player welfare. But by the time protocol begins, the brain injury has already happened. Protocol reduces the risk of poor management after injury. It does not stop the brain being damaged from a head impact ^{[1, 2]}.

Watch: Conventional head protection is not designed to protect the brain.

The limits of concussion protocol

It begins after the impact

The biggest limitation is timing. A player can only be assessed, removed, and monitored after a head impact or suspected concussive event has already taken place. That makes the protocol purely reactive by design ^[2].

Not every brain injury is obvious immediately

Concussion is not always immediately apparent at pitch side. Some players develop concussion signs or symptoms later, and elite processes therefore include follow-up assessment after the initial event ^{[3, 5]}.

Sub-concussions result from an impact of lower force than required to cause a concussion. Sub-concussive impacts are around 500 times more frequent than impacts which result in concussion. A sub-concussion causes damage to the brain without any symptoms.

It focuses on recognised concussion, not total brain impact burden

Concussion protocols are built around suspected concussion events. But the total burden of brain injury in sport is wider than diagnosed concussion alone. Repetitive sub-concussive impacts are associated with neuropathologic changes, neuroinflammation, and neuronal loss in contact and collision-sport athletes, including younger athletes ^{[6, 7]}.

Protocol quality varies by level of sport

Elite sport may have doctors, video review, and formal HIA pathways. Grassroots and school sports rely on coaches, parents, teachers, and volunteers. That makes education and straightforward recognise-and-remove culture even more important, but also means implementation is uneven in the amateur sports world ^[3].

Reduce avoidable head impacts in training

A large share of cumulative exposure can happen in practice rather than only in competition or game play. Coaches can reduce avoidable risk by limiting unnecessary full-contact repetitions, redesigning drills that create repetitive head contact, and being more selective about collision volume across the week ^{[1, 3]}.

Improve technique in contact, aerial challenges, and falls

Safer tackling mechanics, better body position, more controlled aerial contest behaviour, and better falling technique may reduce the chance of awkward or direct head impacts.

Treat suspected concussion with immediate recognition and removal

Although concussion recognition is not primary protection, it is still essential. A player with a suspected concussion should not continue, because further exposure may worsen the brain injury and increase the chance of another hit during a vulnerable period ^{[2, 3]}.

One of the most common mistakes in sport is assuming a player is fine because they look fine immediately after impact. Concussion symptoms can evolve later, which is why education around headache, dizziness, visual disturbance, balance problems, confusion, behaviour change, and sleep disruption remains important ^{[3, 5]}.

30% of children and youths experience persistent post-concussion symptoms, including physical, emotional, cognitive and sleep issues ^[12]. They also have a higher risk of not achieving minimum standards for numeracy and reading in school and demonstrate worse cognitive, planning, and new learning abilities as adults ^[13].

Use a medically supervised graduated return-to-play process

Returning too early adds avoidable risk. The effects a concussion has on the brain can last more than a year ^[8]. However, the return to play in most sports is often no longer than 23 days ^[9], even less for elite sports (7 days in some instances), increasing the risk of further brain injury. Moreover, concussion can cause impairments in balance and neuromotor responses during jumping and landing ^[10], increasing the risk of lower-body injuries (e.g., anterior cruciate ligament injury, lateral ankle sprain, knee injuries and muscle strains) by up to 67% for more than a year following a concussion ^[11].

Take sub-concussive impacts seriously

Not every head impact produces a diagnosed concussion. Repetitive sub-concussive impacts cause damage that accumulates silently, especially in sports with repeated heading, contact, or collisions. A protection strategy that focuses only on diagnosed concussion will miss an essential part of the brain-health picture ^{[6, 7]}.

Why Rezon Halos® should be considered the strongest practical mitigation for concussion risk reduction in sport

If the question is how to reduce concussion risk in sport, the answer should prioritise measures that act at the point where injury risk is generated.

Concussion protocol is essential, but it starts after an actual or suspected injury. Better coaching matters, but it cannot eliminate every unpredictable collision or improve every player’s style of play. Rule enforcement matters, but sport remains fast, contested, and imperfect. Rezon Halos®, by contrast, is designed specifically to reduce rotational force transmission during the impacts that will inevitably still happen ^{[1, 4]}.

That is why Halos® deserves to sit high in the list of practical protection strategies. It addresses the biomechanical event itself, rather than only the medical response that follows it ^[4].

What parents, coaches, schools, volunteers, and athletes can do this week

• Review your concussion removal process and make sure everyone around the player understands it. Confirm that suspected concussion means removal, not observation while play continues ^[3].
• Audit training sessions for repetitive, avoidable head-contact exposure. In many teams, meaningful protection gains come from reducing volume rather than waiting for a dramatic incident ^[1,3].
• Use Rezon Halos® brain protection consistently in both training and competition, especially in sports or positions with repeated contact or aerial exposure. Protection is most relevant when it is worn before the impact occurs and from an early age ^[4].
• Educate athletes and parents about delayed symptoms and sub-concussive exposure. The absence of an immediate diagnosis does not mean the absence of brain injury ^{[5,6, 7]}.