Quick answer. A concussion is a type of brain injury caused by a bump, blow or jolt to the head, face or neck. It is not just ‘getting your bell rung’ and you do not need to lose consciousness to have one. Signs include headache, dizziness, confusion, memory problems, nausea, balance problems and sensitivity to light or sound. The safety rule is ‘when in doubt, sit them out’ – any athlete with a suspected concussion must stop playing immediately. Recovery uses a graded, step-by-step return to learn and return to play. Some symptoms are emergencies: in Singapore, call 995 for an ambulance or go to A&E for worsening headache, repeated vomiting, increasing confusion or drowsiness, seizures, weakness or slurred speech.
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In a medical emergency, or for severe or sudden symptoms such as breathing difficulty, chest pain, fainting or stroke signs, call 995 immediately.
A concussion is a type of brain injury that happens after a sudden bump, blow or jolt to the head, face or neck that makes the brain temporarily not work normally. It is common in contact and collision sports such as rugby, football and martial arts, but can happen in any sport, including from falls.
A concussion is a serious injury and should never be dismissed as simply ‘getting your bell rung’. Crucially, you do not have to lose consciousness to have a concussion, and symptoms are not always obvious straight away. This guide explains how to recognise concussion, the red flags that mean a medical emergency, and how to return safely to learning and sport. The guiding principle throughout is simple: when in doubt, sit them out.
At a glance
| Category | Signs | Action |
|---|---|---|
| Possible concussion | Headache, dizziness, confusion, memory problems, nausea, balance issues, light/sound sensitivity | Stop playing immediately; assess; see a doctor |
| Behaviour/cognition | Looks dazed, slow to respond, irritable, 'not themselves' | Remove from play; do not return same day |
| EMERGENCY red flags | Worsening or severe headache, repeated vomiting, increasing confusion or drowsiness, seizure, weakness/numbness, slurred speech, unequal pupils, neck pain, loss of consciousness | Call 995 (ambulance) or go to A&E now |
| Golden rule | Any doubt at all | When in doubt, sit them out |
What is a concussion? (It's a brain injury)
A concussion is a form of traumatic brain injury caused by a direct blow to the head or a force transmitted to the head, for example from a tackle, collision, fall or whiplash to the neck. The brain is briefly disrupted, causing a range of physical, cognitive and emotional symptoms.
Two myths are worth correcting:
- You do not need to be knocked out. Most concussions occur without any loss of consciousness.
- It is not trivial. Concussion affects how the brain functions and needs proper recognition, rest and a careful return to activity.
How to recognise a concussion
Symptoms can appear immediately or develop over minutes to hours, and not all need to be present. Watch for:
- Physical: headache, dizziness, nausea, balance problems, blurred or double vision, sensitivity to light or sound.
- Thinking/memory: confusion, feeling ‘in a fog’, slowed responses, difficulty concentrating or remembering.
- Emotional/sleep: irritability, feeling more emotional, drowsiness or changes in sleep.
- Observed signs: looking dazed or stunned, unsteadiness, or simply being ‘not themselves’.
'When in doubt, sit them out'
This is the single most important safety rule in sports concussion. If a concussion is even suspected, the athlete must stop playing immediately and not return to play on the same day.
- Continuing to play risks a worse or more prolonged injury.
- A second head impact before the brain has recovered is dangerous (see below).
- Coaches, parents and teammates should err on the side of caution; symptoms can be hidden or downplayed by the athlete.
It is always safer to sit a player out and have them assessed than to risk a second injury.
Red flags: when it is an emergency
Most concussions are not life-threatening, but some signs point to a more serious brain injury that needs emergency care. Call 995 for an ambulance in Singapore, or go to the nearest A&E immediately, if the injured person has any of the following:
- Severe or rapidly worsening headache.
- Repeated vomiting.
- Increasing confusion, agitation, or becoming very drowsy or hard to wake.
- Seizure or convulsion.
- Weakness, numbness or tingling in the arms or legs, or slurred speech.
- Loss of consciousness, unequal pupils, or clear fluid/blood from the nose or ears.
- Neck pain or tenderness after the injury.
Watch closely for the first 24-72 hours, as serious complications usually show within this window.
Graded return to learn and return to play
Recovery follows a stepwise, symptom-guided progression. After an initial period of relative rest, activity is increased gradually, and you only move to the next step if you remain symptom-free.
- Return to learn first: for students, gradually resume schoolwork and screen time, building up to full classes without symptoms returning before adding sport.
- Return to play (stepwise): progress from light aerobic activity, to sport-specific exercise, to non-contact drills, to full-contact practice, and finally to competition.
- Pace it: each stage should be free of symptoms before progressing; if symptoms return, step back and rest before trying again.
- Final clearance to full contact should be guided by a doctor.
Second-impact caution and seeing a doctor
A particular danger is sustaining a second head injury before the first concussion has fully healed. This can lead to more severe and longer-lasting damage, which is why a careful, unrushed return is so important and why no one should return to play while symptomatic.
See a doctor (such as a sports medicine doctor) for any suspected concussion to confirm the diagnosis and guide recovery and return to play. Seek emergency care (995 or A&E) for any red-flag symptoms listed above. When unsure, always choose caution: when in doubt, sit them out.
Related guides
- Best Sports Medicine Clinics in Singapore — our editorial shortlist
- Hamstring & groin strain
- Rotator cuff & shoulder pain
- Stress fractures
Sources
- SingHealth – Concussion
- HealthHub – Head Injuries in Children
- SingHealth – Head Injury
- CDC HEADS UP – Returning to Sports
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- Ankle Sprain Treatment in Singapore
- Common Running Injuries and How to Treat Them in Singapore
- Sports Injury Treatment in Singapore
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