CONCUSSION IN CYCLING: RECOGNITION, RECOVERY AND THE RETURN TO RIDING

You come off the bike and the first thing you do is check your body. Hands — scraped but working. Shoulder — sore but moving. Knee — bloody, stinging, probably fine. You stand up, brush yourself down, look at the bike. Derailleur hanger intact. Bars straight. Okay. You get back on and ride home.

Nobody checks the one thing that actually matters. The brain.

I have watched this play out dozens of times. A rider crashes, walks it off, maybe goes to a minor injuries unit for the road rash, then turns up to the next group ride five days later. And the whole time, they've had a headache they've been putting down to stress, slightly blurred vision they've been putting down to tired eyes, and irritability they've been putting down to frustration at missing training. They had a concussion. They just never looked for it.

Here's the thing nobody tells you about concussion in cycling: it is far more common than the sport acknowledges, significantly harder to recognise than a broken bone, and the consequences of mismanaging it are orders of magnitude worse than riding on a cracked collarbone. A collarbone heals in eight weeks regardless. A badly managed concussion can change the next twelve months of your life.

This is everything you need to know. What concussion actually is, how to spot it, when to get to hospital, how to come back properly, and what masters cyclists specifically need to understand about recovery timelines.

What a concussion actually is

Let me be really clear about this, because the common understanding is wrong.

Most people think concussion means you hit your head on something hard and your brain gets bruised. That is not what happens. A concussion is a functional injury — a disruption to how the brain works, not structural damage you can see on a scan. Your CT will usually come back clean. Your MRI will look normal. And you will still have a concussion.

The mechanism is rotational acceleration. When your head changes speed or direction suddenly — which happens in almost every cycling crash — the brain, which sits in cerebrospinal fluid inside your skull, continues moving after the skull stops. This creates shearing forces across the brain tissue, disrupting the normal electrochemical signalling between neurons. The result is a cascade of metabolic dysfunction: ions leak across cell membranes, energy demands spike, blood flow regulation goes haywire, and the brain enters a state of vulnerability that can last days to weeks.

Here's where it gets really interesting — and important for cyclists. You do not need to hit your head to get a concussion. Any crash that produces rapid acceleration or deceleration of the head can do it. A high-speed washout where your body stops but your head whips sideways. Going over the bars and landing on your shoulder with your neck snapping forward. Even a hard rear-end collision that jolts your entire body. If the forces acting on your skull are sufficient to create rotational movement of the brain inside it, concussion is possible.

The 6th International Conference on Concussion in Sport, led by McCrory and colleagues in Amsterdam, defined concussion as a "traumatic brain injury induced by biomechanical forces" and explicitly noted that it does not require direct impact to the head and does not require loss of consciousness. That second point is critical. The old idea that you need to be knocked out to have a concussion is dangerous nonsense. Fewer than 10% of sport-related concussions involve loss of consciousness.

Why helmets help but are not the full answer

Your helmet is doing a brilliant job at the thing it was designed to do: prevent skull fractures and catastrophic focal brain injuries. The expanded polystyrene foam absorbs linear impact energy — the straight-line force of your head hitting tarmac — and distributes it over a larger area. Without a helmet, that concentrated force cracks bone. With one, the energy is dispersed and deceleration is slowed.

But here is the gap. Traditional EPS helmets are less effective against rotational forces. And rotational forces are the primary mechanism of concussion. When your head hits the ground at an angle — which is how most cycling crashes play out — the helmet grips the surface and your head rotates inside it. The linear energy is absorbed. The rotational energy is not.

This is the problem that MIPS (Multi-directional Impact Protection System) and similar technologies attempt to address. MIPS uses a low-friction liner inside the helmet that allows 10-15mm of rotational movement during impact, reducing the rotational acceleration transmitted to the brain. WaveCel, SPIN, and Kali's LDL system work on similar principles through different mechanisms.

Do they work? The independent data from Virginia Tech's helmet rating system and Folksam's insurance research in Sweden suggests that MIPS and equivalent technologies do reduce rotational acceleration in laboratory testing, typically by 30-40% compared to conventional helmets. That is meaningful. It is also not a guarantee. No helmet eliminates concussion risk. Any marketing that implies otherwise is irresponsible.

What this means practically: wear a helmet with rotational-impact technology. It improves your odds. But do not let it make you complacent about concussion risk. The helmet reduces severity. It does not make you immune.

Recognising concussion on the road

This is where your riding partners become critical. Because here's the problem: the hallmark feature of concussion is impaired self-assessment. A concussed brain cannot reliably evaluate whether it is concussed. The person you need to diagnose the injury is the person least capable of diagnosing it.

Immediately after a crash involving any head or neck impact, look for:

• Confusion or disorientation — asking the same question repeatedly, not knowing where they are, unable to recall the route
• Vacant or glassy-eyed stare
• Slow or slurred speech
• Loss of consciousness, even briefly
• Difficulty standing or walking straight
• Unequal pupil size (one bigger than the other — this is a red flag for something more serious than concussion)
• Amnesia — they cannot remember the crash itself, or events immediately before it
• Nausea or vomiting

Symptoms that may develop over the following hours:

• Headache that worsens rather than improves
• Dizziness or a feeling that the world is moving
• Sensitivity to light or noise
• Difficulty concentrating or thinking clearly — the "foggy" feeling
• Irritability or emotional volatility out of character for that person
• Fatigue disproportionate to the effort
• Sleep disturbance — either excessive drowsiness or inability to sleep
• Tinnitus (ringing in the ears)

The principle used across professional sport, from rugby to the NFL to British Cycling, is simple: if in doubt, sit it out. If there is any suspicion of concussion, the rider does not get back on the bike. Not to "test it." Not to "see how it goes." Not to ride slowly home. They stop. Someone calls for a lift. The bike goes in a car.

What your riding partners should know: if someone crashes and seems confused, asks the same thing twice, or says they feel "a bit off," that person does not get to make the decision about whether they continue. You make it for them. This is not overbearing. This is exactly what the Sport Concussion Assessment Tool (SCAT6) — the gold-standard sideline assessment used by McCrory, Meeuwisse and the concussion consensus group — recommends for non-medical personnel. Any observed sign of concussion means immediate removal from activity.

Red flags: when it is A&E immediately

Most concussions are managed at home with rest and the graduated return protocol. But some presentations indicate something more serious — a brain bleed, a skull fracture, or cervical spine injury — and require emergency care.

Call an ambulance if any of these are present:

• Loss of consciousness lasting more than 30 seconds. Brief loss of consciousness (a few seconds) is common in concussion. Prolonged unconsciousness suggests more significant injury.
• Seizure activity. Any convulsive movement, jerking, or tonic posturing after the impact. Even a single brief seizure after head injury requires emergency assessment.
• Worsening headache. A headache that progressively worsens despite paracetamol, particularly in the first 6-12 hours, can indicate expanding intracranial haemorrhage.
• Repeated vomiting. One episode of nausea is common with concussion. Multiple episodes of vomiting, especially projectile vomiting, is a red flag.
• Clear fluid from the nose or ears. This may be cerebrospinal fluid leaking through a fracture in the skull base. It looks like watery nasal discharge but does not behave like normal mucus — it often runs continuously and may have a sweet taste (though obviously do not ask someone to taste their nasal discharge as a diagnostic test).
• Increasing confusion. A concussed person who initially seems lucid but becomes progressively more confused over minutes to hours — the so-called "lucid interval" — may have an epidural or subdural haematoma.
• Weakness or numbness on one side of the body. This suggests focal brain injury rather than diffuse concussion.
• Inability to recognise people or places.

Let me be really clear about this: if any of these are present, do not put the person back on a bike and ride to hospital. Do not drive them yourself if you can avoid it. Call 999. The person may deteriorate en route, and you cannot manage that in a car. Paramedics can.

For less severe presentations — headache, mild confusion that clears within minutes, nausea without vomiting — the person should still be assessed by a GP within 24 hours. Describe the mechanism of injury (crash speed, what they hit, helmet damage) and any observed symptoms. The GP can arrange onward referral or imaging if needed.

The graduated return to riding protocol

This is the framework. It is based on the Concussion in Sport Group consensus statement (McCrory et al., 2023) and adapted by every major sporting body worldwide. It is not optional. It is not something you do roughly. It is the protocol.

Stage 1: Symptom-limited activity (24-48 hours minimum)

Complete cognitive and physical rest for the first 24-48 hours. This means no training, no work if possible, limited screen time, limited reading. Your brain's energy budget is compromised — every cognitive demand you place on it competes with the energy it needs for repair. Sleep as much as your body wants. Stay in a quiet, dimly lit environment if light and noise bother you.

After the initial rest period, brief walks and gentle daily activities are permitted as long as they do not worsen symptoms. You stay at this stage until you have been completely symptom-free at rest for a minimum of 24 hours. Not "mostly fine." Symptom-free.

Stage 2: Light aerobic exercise

Gentle walking or stationary cycling at below 70% of maximum heart rate for 15-20 minutes. No resistance training. No interval work. The purpose is to increase heart rate mildly and confirm that basic exertion does not trigger symptoms. If your headache returns, if you feel dizzy, if the fogginess comes back — stop. Drop back to Stage 1 and wait another 48 hours before trying again.

Stage 3: Sport-specific exercise

Turbo trainer sessions at moderate intensity. You can increase duration and introduce some tempo work, but no high-intensity efforts. No outdoor riding yet — the cognitive demands of traffic, navigation, and hazard perception are too high at this stage. Minimum 24 hours at this stage before progressing.

Stage 4: Non-contact training

Outdoor riding on quiet, familiar roads. Progressive intensity up to and including threshold efforts. This stage reintroduces the full cognitive load of cycling — reading the road, reacting to traffic, maintaining spatial awareness. If you notice any symptom return, even subtle fogginess or mild headache, drop back.

Stage 5: Full training

Normal training programme. Group rides, intervals, the full range of intensity and duration. Monitor for any symptom return over 24-48 hours.

Stage 6: Return to competition

Racing, sportives, time trials — anything with full intensity and the additional cognitive and physiological stress of competition.

The rules that govern this:

• Minimum 24 hours at each stage before moving to the next
• Any return of symptoms at any stage means you drop back to the previous stage and wait 48 hours before trying to progress again
• The absolute minimum from injury to full return is approximately 10-14 days, and many adults take longer
• If symptoms persist beyond 14 days, seek referral to a sports medicine physician or concussion specialist

This feels conservative. It is meant to. The protocol exists because the alternative — guessing when you're ready based on how you feel — produces catastrophic outcomes often enough to matter.

Second impact syndrome: why the protocol is non-negotiable

I am going to keep this factual because the facts are sufficient.

Second impact syndrome occurs when a person sustains a second concussion before the first has fully resolved. The brain, still in its metabolically vulnerable state from the initial injury, loses its ability to regulate blood flow. The result is rapid, diffuse cerebral oedema — swelling across the entire brain. Intracranial pressure rises catastrophically. The brainstem herniates.

The mortality rate is approximately 50%. Among survivors, the rate of permanent severe disability is close to 100%.

It is rare. The exact incidence is debated because retrospective diagnosis is difficult, but it is documented in the medical literature across multiple sports. What is not debated is the mechanism: a brain that has not recovered from one concussion is vastly more vulnerable to a second.

This is the single reason the graduated return protocol exists. Not because rest makes concussion more comfortable — although it does. Not because the stages are evidence-based — although they are. But because returning to activity while still symptomatic puts you at risk of second impact syndrome, and second impact syndrome is not something you recover from.

Dr Robert Cantu at Boston University, one of the leading researchers in sports concussion, has been writing about this since the 1990s. His position has not changed: no athlete at any level should return to contact or collision-risk activity until they are completely asymptomatic at rest and during exertion. Cycling is a collision-risk activity. The road is not soft.

Helmet replacement: the non-negotiable rule

Any helmet involved in a crash must be replaced. Full stop. No exceptions. No "it looks fine." No "it was only a low-speed crash."

Here's why. The EPS (expanded polystyrene) foam that lines your helmet works by crushing on impact. That crushing absorbs kinetic energy that would otherwise be transferred to your skull. But EPS does not bounce back. Once compressed, the foam stays compressed. It cannot absorb energy a second time. A helmet that has been impacted is structurally compromised even if the shell looks pristine. The next impact will transfer significantly more force to your head.

You cannot see this with your eyes. There may be no crack in the outer shell. No visible dent. But the internal structure has done its job and cannot do it again. The analogy is a car crumple zone — it works once, spectacularly, and then the car is a write-off even if the doors still open and the paint looks fine.

When to replace even without a crash:

• After five years. UV exposure and temperature cycling degrade EPS over time. Most manufacturers recommend replacement every 3-5 years of regular use.
• After any significant drop onto a hard surface — off a shelf, off the roof of a car.
• If the retention system (straps, buckle, dial adjustment) no longer holds the helmet securely in position.

On MIPS and rotational-impact technology: if your current helmet does not have a rotational-impact liner and you are replacing after a crash, this is the time to consider upgrading. The price premium for MIPS or equivalent is typically 15-25% over a comparable non-MIPS helmet. Given that rotational acceleration is the primary mechanism of concussion, that premium is worth paying.

Several manufacturers — including Giro, POC, Specialized, and Lazer — offer crash replacement programmes where you can replace a crashed helmet at a reduced cost within a specified period of purchase. Check with the manufacturer before buying new at full price.

Long-term management for masters cyclists

Here's where it gets really important for the audience reading this. If you are over 40, your concussion recovery will be different from a 25-year-old's. Not might be. Will be.

The research is consistent on this. Dr Willie Stewart at the University of Glasgow has published extensively on age-related vulnerability to concussion, and the data shows that older adults take longer to recover across every measured outcome — symptom resolution, cognitive recovery, return to baseline neuropsychological function. Where a 20-year-old typically returns to baseline within 7-10 days, adults over 40 commonly require 2-4 weeks. Some take longer.

The reasons are physiological. Cerebral blood flow regulation becomes less efficient with age. Neuroplasticity — the brain's ability to reorganise and compensate — declines. The metabolic recovery cascade that follows concussion takes longer to resolve. And crucially, the brain's tolerance for cumulative injury decreases. A 45-year-old who has had three concussions over a lifetime is in a materially different position from a 22-year-old with the same history.

What this means practically:

• Be more conservative with the graduated return protocol. If the stages call for a minimum of 24 hours, give yourself 48. If 48, give yourself 72. There is zero cost to being slower. There is significant cost to being faster.
• Take cognitive symptoms seriously. If you are back at work but finding it harder to concentrate, struggling with complex tasks, or losing your thread mid-conversation more than normal — you are not ready for Stage 3 of the return protocol, regardless of whether your headache has gone.
• Consider baseline cognitive testing. This involves a battery of tests — reaction time, processing speed, memory, attention — that establish your personal normal. Post-concussion, the same tests can be compared against your baseline rather than against population averages. This is standard practice in professional rugby, the NFL, and Premier League football. It is increasingly available through sports medicine clinics, and for a masters cyclist who rides regularly and accepts crash risk, it is worth having on file.
• Know your concussion history. If you have had multiple concussions, your threshold for the next one is lower and your recovery time is likely to be longer. Three or more documented concussions is the point at which most sports medicine guidelines recommend a specialist neurological review to discuss ongoing risk.
• If symptoms persist beyond four weeks, you are in post-concussion syndrome territory. This is not a sign of weakness or psychological fragility — it is a recognised medical condition with a defined diagnostic criteria and treatment pathways. Referral to a neurologist or concussion-specialist sports medicine physician is appropriate. The treatment usually involves a combination of graduated exercise therapy, vestibular rehabilitation if dizziness is a feature, and sometimes cognitive behavioural approaches for the anxiety that frequently accompanies prolonged symptoms.

What to carry, who to tell, and when to get help

Practical things. The things that make a difference when the crash actually happens.

In your jersey pocket:

Carry an emergency contact card. A small laminated card — the size of a business card — in your middle jersey pocket or saddle bag with the following information:

• Your name
• Your blood type (if you know it)
• Emergency contact name and phone number
• Any allergies (especially drug allergies)
• Any medications you take regularly
• Any medical conditions (asthma, diabetes, epilepsy)

The reason is simple. If you are concussed, you may not be coherent enough to tell a paramedic these things. If you are unconscious, you certainly cannot. Your phone is likely locked, potentially smashed, and even if someone can access it, they do not know which contact is your emergency contact unless you have set up ICE contacts — and most people have not.

A physical card in a standard location is findable, readable, and does not need a password. It is a two-minute job that could save your life.

What to tell your GP:

If you attend your GP after a suspected concussion, give them this information:

• The speed you were travelling at the time of the crash
• The mechanism — did you hit your head directly, or was it a whiplash-type movement?
• Did you lose consciousness, and if so, for how long?
• Did anyone observe you being confused, asking repeated questions, or behaving unusually?
• What symptoms you have now and when they started
• Any previous concussion history
• Whether you were wearing a helmet and whether it was damaged

GPs are generalists. They cannot be experts in everything. Giving them a clear clinical picture helps them make better decisions about whether to refer you for imaging, observation, or specialist review.

When you need a sports medicine referral:

• Symptoms that persist beyond 14 days
• Symptoms that are worsening rather than improving
• Any new symptom appearing days after the initial injury
• Three or more lifetime concussions
• You are a competitive athlete and need a structured, medically supervised return-to-sport programme
• You are experiencing anxiety, depression, or personality changes that you or those close to you have noticed since the injury

A sports medicine physician with concussion experience — or a neurologist — can arrange formal neuropsychological testing, vestibular assessment, and a tailored rehabilitation programme. This is not excessive for a brain injury. It is appropriate.

The bottom line

Concussion is the injury cyclists do not check for, do not talk about, and do not manage properly. Every other part of a crash gets attention. The road rash gets dressed. The collarbone gets X-rayed. The bike gets inspected for frame damage. But the brain — the organ that controls every other function, the thing without which none of the rest matters — gets nothing. A vague "I feel alright" and back on the bike by Thursday.

The good news is that this is fixable. Concussions, when recognised and managed properly, resolve. The graduated return protocol works. The vast majority of people make a complete recovery and ride for decades afterwards without issue. The process requires patience, especially for riders over 40, and it requires the discipline to follow a protocol rather than relying on how you feel. But it works.

The only scenario where it does not work is the one where you do not follow it. Where you ride through the headache, dismiss the fogginess, and go back to the group ride because you do not want to lose fitness. That is the scenario where rare but devastating complications become possible. And no race, no training block, no Strava segment is worth that risk.

Wear a helmet with rotational-impact technology. Replace it after any crash. Learn the signs of concussion so you can recognise them in yourself and your riding partners. Carry an emergency contact card. And if you crash and anything feels off — anything at all — sit it out. Get assessed. Follow the protocol.

Your brain does not get a crash replacement programme.

If you are working through a concussion recovery or want to talk to riders who have dealt with crashes and comebacks — the Roadman Cycling community on Skool is the place. Real riders, real experience, no nonsense. People who have been through it and come out the other side.