Concussion: Symptoms, Recovery, and Treatment

What exactly is a concussion?

A concussion is an injury caused by a force transmitted to the brain that disrupts its functioning. It is classified as a mild traumatic brain injury, or MTBI. Rehabilitation encompasses the care and exercises that help a person regain their abilities and resume their activities. Rehabilitation experts allow the term “concussion” to be used for a mild TCCL when brain imaging results are normal or when such tests are not necessary.^[12] A sudden acceleration or deceleration of the head can cause the brain tissue to stretch, even without a direct blow to the head.

The term “mild traumatic brain injury” (MTBI) covers a broader category of injuries. Some cases of MTBI show abnormalities visible on imaging tests. The word “mild” describes the initial severity of the injury; it does not mean that the symptoms are imaginary or that they will always go away quickly.

The brain is surrounded by a protective fluid. During sudden acceleration, its tissues can shift and become distorted. These forces can stretch neurons—the cells that transmit information—and their extensions. The injury can alter both their function and their microscopic structure. It also triggers the movement of ions—small charged particles—and the release of glutamate, a substance that transmits messages between cells. These changes increase the brain’s energy requirements. This set of reactions is known as the metabolic cascade. Many of these mechanisms have been studied in experimental models; standard imaging tests do not reveal all of these changes.^[14]

Why might brain images appear normal?

A concussion can disrupt brain function without causing any visible damage on standard tests. Therefore, normal imaging results do not rule out all microscopic changes. A review of diagnostic studies also shows that no single test can detect all concussions.^[15]

Computed tomography (CT), often called a scan, uses X-rays to produce images of the brain. Magnetic resonance imaging (MRI) uses a magnetic field. These tests can detect certain lesions, but a normal result does not rule out a concussion. The healthcare provider chooses the imaging modality based on the observed signs and the risk of another injury.

The severity of a brain injury is assessed based on the patient’s level of consciousness, memory of events, and clinical examination—that is, the observations and tests conducted by the healthcare professional. Imaging studies and follow-up care provide additional information. The duration of symptoms alone does not determine the initial severity.

What are the causes and mechanisms of a concussion?

A concussion occurs when the brain undergoes rapid acceleration inside the skull. The most common causes are contact sports, falls, traffic accidents, and direct blows to the head. However, the order of these causes is not fixed: it varies depending on age, living environment, and the type of data collected. The summary by the World Health Organization Collaborating Center, which reviewed 121 studies, lists falls and traffic collisions among the common causes of mild traumatic brain injury^[16]. Linear and rotational movements can distort brain tissue.

Most common causes

• Ice hockey (checking)
• Football (tackled)
• Soccer (heading, collision)
• Cycling (fall)
• Downhill skiing and snowboarding

• Falls (stairs, ladder, ice)
• Car or motorcycle accidents
• Direct blows to the head
• Workplace accidents

Important fact: A direct blow to the head is not necessary. A sudden acceleration of the body may be enough. In fact, the international consensus defines a concussion as an injury caused by a blow to the head, neck, or body that transmits force to the brain^[1], and the accelerations measured in confirmed cases vary greatly from person to person^[13]. For example, a tackle in football without head contact can cause a concussion if the head undergoes rapid acceleration.

The coup-contrecoup mechanism

An impact can cause a contusion—an area of bruised brain tissue—on the side of the blow or on the opposite side. This is referred to as a direct blow or a counter-blow. This description of localized injuries does not cover all concussions. A concussion can occur without a visible contusion, caused by forces that distort the brain. The American Institute of Neurological Disorders explains these different types of brain injuries.

Rotational forces

A rapid rotation of the head can cause deformations in brain tissue. Different regions of the brain do not all move in the same way. Axons—the long extensions of neurons—can then become stretched, disrupting the transmission of signals. Research is investigating the role of these deformations and their links to concussions.^[17]

Accelerations during straight-line movement and during turns vary greatly among individuals with a confirmed concussion. A 2017 review relied primarily on data from American football. These measurements alone are not sufficient to determine whether a person has suffered a concussion. Clinical evaluation remains necessary.^[13]

What are the symptoms of a concussion?

A concussion can cause headaches, dizziness, fatigue, and difficulty thinking, managing emotions, or sleeping. Symptoms fall into four categories: physical, cognitive, emotional, and sleep-related. Cognitive symptoms affect thinking, memory, and concentration. Even a single symptom following an impact is enough to raise suspicion of a concussion.

Physical symptoms

Possible physical symptoms:

• Headaches
• Dizziness or lightheadedness
• Nausea or vomiting
• Excessive fatigue
• Blurred or double vision; new-onset double vision following an impact requires urgent evaluation
• Sensitivity to light (photophobia)
• Sensitivity to noise (phonophobia)
• Balance problems
• Tinnitus (ringing in the ears)

Cognitive symptoms

Cognitive symptoms affect your ability to think clearly:

• Difficulty concentrating
• Memory problems
• Feeling confused or mentally foggy
• Slowness in processing information
• Difficulty finding words
• Slowed reaction time

Emotional Symptoms

Emotional symptoms are very real and are part of the clinical picture of a concussion:

• Irritability
• Sadness or depressive mood
• Anxiety
• Mood swings
• Feeling "not like yourself"

For a more comprehensive overview of these symptoms, read our article , “Concussions Are More Than Just Headaches.”

Sleep Disturbances

Sleep is often disrupted after a concussion:

• Sleeping more than usual
• Sleeping less than usual
• Difficulty falling asleep
• Unrefreshing sleep

When do symptoms appear?

Symptoms may appear immediately after the impact or develop gradually over the following hours and days. In a study of 48 concussions among players wearing helmets equipped with sensors, symptoms were immediate in 24 cases, delayed in 11 cases, and of indeterminate timing in 13 cases; the diagnosis was often made later, with half of the diagnoses made within 17 hours and the other half later^[19]. This is why it’s important to keep an eye on the person after a potential impact—not just at the moment of the hit.

Important: Just because you feel fine in the minutes following an impact doesn't mean you don't have a concussion. If you suspect you have a concussion, leave the game immediately and get evaluated. Do not return to play on the same day as long as a concussion is suspected or confirmed.

How is a concussion diagnosed?

The diagnosis of a concussion is based on the circumstances of the injury, the symptoms, and the clinical examination. No single laboratory or imaging test is sufficient on its own to confirm or rule out a concussion. A review of studies found that concussion assessment tools used in sports, known as SCAT, perform well, although no single test is perfect on its own.^[15] The evaluation must always combine several elements. These tools are particularly useful in the first few days; follow-up also assesses vision, balance, neck status, and persistent symptoms.^[20]

Clinical evaluation

A healthcare professional trained in concussion will ask you about:

• The circumstances of the impact (what, when, how)
• Your current symptoms and how they have changed
• Any loss of consciousness or amnesia—that is, a memory lapse surrounding the accident
• Your history of concussions
• Your existing health problems

Standardized Assessment Tools

The SCAT6, the sixth edition of the sports concussion assessment tool, helps professionals evaluate athletes ages 13 and older. The Child SCAT6 is designed for children ages 8 to 12. The SCAT6 is primarily used within the first 72 hours and up to one week after the injury. The SCOAT6, a clinical assessment tool, aids in follow-up after the initial days. The SCAT6 form includes the following elements, among others. It does not replace clinical judgment.

Additional tests

Your physiotherapist or doctor might perform additional tests:

Vestibular Evaluation: The vestibular system connects the balance organs in the inner ear to nerves and regions of the brain. These tests help identify the causes of dizziness and balance problems. See our guide on vertigo and dizziness to learn more.

Oculomotor evaluation: These tests assess eye movements. They can evaluate convergence—the ability to focus both eyes on a nearby target—tracking of a moving target, and saccades—rapid eye movements.

Cervical evaluation: to determine whether the neck is contributing to the symptoms. The same impact can injure both the neck and the brain, so a whiplash injury may accompany a concussion. See our guide on whiplash to understand this related injury.

When is imaging necessary?

A CT scan and an MRI alone do not confirm a concussion. They may be necessary to check for other injuries, such as bleeding, depending on the symptoms observed. The warning signs listed in the section “Warning Signs: When to Go to the Emergency Room” require immediate medical evaluation.

What are the stages of recovery from a concussion?

Recovery from a concussion begins with relative rest, followed by a gradual resumption of activities until a return to normal activities. The three phases below are used to structure this process. Their duration depends on symptoms, tolerated activities, and clinical examination. Relative rest already allows for light activities; it does not require stopping all activities.^[1]

Phase 1: Relative rest (24 to 48 hours)

The first 24 to 48 hours are crucial¹. “Relative rest” means:

• Light activities that do not significantly increase your symptoms
• Short walks
• Reading for short periods
• Light conversations
• Light cooking

• Activities that significantly worsen your symptoms
• Intense sports and physical activities
• Prolonged screen time (television, phone, computer)
• Alcohol and recreational drugs
• Demanding cognitive tasks

Important: Complete rest in the dark is no longer recommended. Light activities during the first two days, followed by appropriate endurance exercise—such as walking or using a stationary bike—are part of the recovery process. A review reports that prescribed exercise between the 2nd and 14th day after a sports-related concussion is beneficial.^[23] Another review of 19 studies involving more than 4,000 people found that prescribed rest had a slight adverse effect on symptoms compared to active interventions.^[24] Stay active within the limits specified by your healthcare professional.

Phase 2: Gradual Resumption

A gradual return to activity allows you to move around and resume certain tasks before your symptoms have completely disappeared. A slight, brief increase in pain may be acceptable: no more than 2 points on a scale of 0 to 10, lasting less than an hour. If the increase exceeds this limit, take a break until the pain returns to its previous level, then reduce the duration or intensity. Your healthcare professional will guide this progression.¹The INESSS guide distinguishes between resuming mental activities and resuming physical activities.

• Light reading or reflection activities, with the duration increasing based on tolerance
• Half-days at school or work
• Full days with accommodations
• Normal return

• Walking or using a stationary bike, starting with light exercise and then moving to moderate exercise
• Light running or sport-specific individual exercises that do not pose a risk of a blow to the head
• Team practices (non-contact)
• Full contact practices
• Return to play or competition

Before engaging in high-risk activities: Symptoms and abnormal findings on examination related to a concussion must have resolved, including during and after exertion. Professional clearance is required before engaging in activities that involve the risk of collision, a fall, or a blow to the head. The steps detailed below specify when to progress and when to take a step back.

Phase 3: Full Recovery

Following a sports-related concussion, a review reports that symptoms resolve after an average of 14 days and that athletes return to sports after nearly 20 days. Results vary widely across studies. Approximately 93% of athletes had resumed their studies without any new accommodations within 10 days.^[21] A review of studies on adults notes that up to 30% of people who have experienced a mild traumatic brain injury may develop persistent symptoms. This figure indicates an order of magnitude, not the exact probability for each individual.^[22] A return to sports without restrictions requires:

• No concussion-related symptoms at rest or during physical activity
• Resolution of memory or concentration difficulties and other concussion-related symptoms observed during the examination
• Clinical evaluation confirming recovery and progression completed
• Authorization from a licensed professional prior to engaging in high-risk activities; the specific requirements in Quebec are outlined below

Work and school may resume with accommodations during the recovery phase. Work at heights or involving other risks requires guidance tailored to those specific tasks. For student-athletes, the INESSS guidelines call for a full return to intellectual activities—including studies—without accommodations prior to Stage 4 of the return to sports.

Our article, “Dealing with a Concussion One Step at a Time,” details this process.

What are the treatment options for a concussion?

Treatment for a concussion involves a brief period of relative rest, a gradual return to activities, and care tailored to the issues identified during the evaluation. Rehabilitation may focus on balance, eye movements, and neck mobility. Appropriate endurance exercise aids recovery from a sports-related concussion.^[23] For persistent symptoms, a review of 12 studies describes this approach as promising. The programs varied widely and often included other forms of care, which limits the conclusions regarding exercise alone.^[25]

Initial relative rest

Relative rest during the first 24 to 48 hours allows the brain to begin healing. Limit intense stimulation while remaining moderately active.

Active Rehabilitation

Scientific understanding has changed: active treatment is now favored over extended rest. Active approaches include:

Appropriate endurance exercise: Light activity, such as walking, can be started within the first 24 to 48 hours if it does not significantly worsen symptoms. A prescribed exercise program can then begin between 2 and 10 days later, depending on the evaluation.¹ The healthcare professional adjusts the intensity to prevent it from exceeding the mild and brief limit described above.

Vestibular rehabilitation: Exercises can help people with dizziness or balance problems. The vestibular system includes structures in the inner ear, nerves, and regions of the brain. A review of seven randomized controlled trials found a reduction in daily difficulties related to dizziness. The results regarding balance and other symptoms are less consistent. The studies are few in number and vary widely from one another.^[26]

Eye movement rehabilitation: The exercises depend on the visual problem identified during the evaluation. In 2021, a review found no eligible comparative trials on this intervention; its recommendation was based on expert opinion.^[27] A 2024 review of 12 studies in adults observed possible improvements, though confidence in the results was low due to the studies’ limitations.^[28]

A more recent trial, CONCUSS, provides evidence for a specific problem: difficulty focusing both eyes together on a nearby target. It involved participants aged 11 to 25 who had this disorder and had been experiencing symptoms for 4 to 24 weeks. After six weeks, 46 out of 52 participants who received immediate treatment showed improvement on two convergence tests, compared with 4 out of 52 in the wait-and-see group. The program included two weekly clinic sessions, in addition to standard care. This result pertains specifically to this visual disorder and this program; it does not measure recovery from all concussion symptoms.^[36]

Cervical treatment: The same impact can affect both the head and the neck. A neck injury may therefore accompany a concussion. That is why a physical therapy evaluation also examines the cervical region, and neck treatment may be part of the treatment plan when headaches persist.¹⁰Physical therapy for neck pain can be part of a personalized treatment plan when the evaluation identifies a neck issue. If you also have persistent headaches, consult our guide on headaches and cephalalgia. When these headaches originate in the neck, they are referred to as cervicogenic headaches.

Psychological Treatment

Anxiety, stress, and depressive symptoms are common after a concussion. Psychological support may be part of the treatment plan, especially if symptoms persist. A statistical synthesis of several studies shows that symptoms that persist after a concussion are associated with a significantly higher likelihood of depressive symptoms^[29]. Psychological support is among the recommended options. The authors remain cautious, as the limitations of the studies reduce confidence in the results^[27].

How Does Physiotherapy Help After a Concussion?

Physical therapy following a concussion helps guide a return to normal activities and addresses any issues with balance, eye movement, or neck movement identified during the evaluation. Not everyone experiences these issues. The physical therapist will select exercises, provide advice, and offer treatment based on your symptoms and goals.

The Complete Assessment

Your physiotherapist will conduct a detailed assessment including:

Symptom Assessment: Questionnaires with the same questions at each follow-up visit to measure your symptoms and how they change over time.

Vestibular evaluation: tests of balance and the mechanisms that stabilize eye movement when the head moves. These functions involve the inner ear and the brain.

Oculomotor Evaluation: Tests of eye movements, convergence, and visual tracking.

Cervical Assessment: An examination of your neck's range of motion, strength, and sensitivity.

Exercise Test: An assessment of your exercise tolerance on a treadmill or stationary bike.

Treatment for Vestibular Problems

At a specialized clinic, combined balance and eye movement disorders affected 28.6% of the young people seen within 30 days of a concussion. They affected 62.5% of those who had had at least three symptoms for a month or longer.^7[7] Another pediatric study also examined these disorders and the factors associated with them.⁸ These specialized clinic groups do not represent all young people with concussions. Vestibular rehabilitation may include:

• Gaze stabilization exercises (fixing your eyes on a target while moving your head)
• Habituation exercises (gradual exposure to movements that provoke symptoms)
• Balance training (on unstable surfaces, with eyes closed)

In a trial involving adolescents and young adults with persistent symptoms, 11 out of 15 participants in the group receiving neck and balance treatment were medically cleared to resume sports within eight weeks, compared with 1 out of 14 in the comparison group, which received the standard of care specified by the trial⁹. This randomized trial involved 31 participants aged 12 to 30 who had persistent dizziness, neck pain, or headaches^[9]. This is a small, specific group, not all cases of concussion. Other trials in adults yield more nuanced results.

These exercises are part of vestibular physical therapy, which treats balance issues and dizziness.

Treatment for Oculomotor Problems

Vision problems are common: difficulty focusing, double vision, light sensitivity. Oculomotor exercises may include:

• Convergence exercises (focusing both eyes on a nearby target)
• Saccade exercises (quickly shifting your gaze)
• Pursuit exercises (following a moving target)

Neck Treatment

The neck may be injured at the same time as a concussion. When the head undergoes a sudden acceleration, the neck also takes the brunt of it. That is why a neck evaluation is part of the follow-up care after a concussion.¹⁰ Cervical physical therapy includes:

• Joint mobilization: movements guided by a physical therapist to improve mobility
• Manual techniques targeting the neck muscles to provide short-term relief
• Exercises to strengthen the neck and improve control over its movements
• Tips for temporarily adjusting positions that worsen your symptoms

The neck can contribute to headaches and dizziness after a concussion. A review of studies reports numerous similarities between whiplash and mild brain injury, and notes that a disorder of the neck joints can exacerbate neck pain and headaches when symptoms persist^[10]. That said, the neck alone does not explain all headaches or dizziness following a concussion. It is an aspect to evaluate as part of care. For more information, see our guide on neck pain.

Following a traffic collision, a study tracked individuals who were seen in the emergency department for whiplash-type injuries. Of the 480 individuals who responded to the three follow-up surveys, 128—or 27%—reported neck pain at 1, 3, and 12 months.^[11] When a concussion occurs in a traffic accident, evaluating the neck remains important, even if symptoms involving the head tend to draw the most attention.¹¹

In this study, significant psychological distress measured after the accident and widespread pain present before the accident were associated with more persistent neck pain. These associations do not prove that stress alone causes the pain. Discussing sleep, stress, and previous pain helps tailor follow-up care.¹¹

The movement resembles that of whiplash: the head is thrown first to one side and then to the other, and the neck absorbs the impact. In fact, a single accident can cause both at the same time. However, they are not two names for the same injury: a systematic review finds similarities in mechanism and symptoms, but also differences, with no clear boundary between the two, and each requires its own assessment^[10].

Return-to-Play Protocol

Your physical therapist can guide you through a gradual return to sports. The steps below summarize the INESSS guidelines and the international consensus. Each step requires at least 24 hours. Progress also depends on the clinical evaluation.

In stages 1 through 3, an increase of no more than 2 out of 10 for less than an hour may be acceptable. If it exceeds this limit, stop the exercise and try again the next day at an appropriate level. Before stage 4, concussion-related symptoms and abnormalities must have resolved, even during exertion. The INESSS guide also requires that you have fully resumed intellectual activities, without any modifications, before this stage. Authorization is required before engaging in any activity that carries a risk of head impact, including earlier if your sport involves this risk. If symptoms return during stages 4 through 6, return to stage 3 and consult your healthcare professional before resuming high-risk activities. The principles of returning to sports after an injury also include a gradual, tailored progression.

In Quebec, a trained physical therapist who regularly treats this type of condition may authorize a return to high-risk sports activities following clinical recovery. A physician or a specialized nurse practitioner (IPS) must be involved in the decision when symptoms persist. A new medical evaluation is also required if there are warning signs, abnormal worsening of symptoms, a medical condition that may interfere with the neurological examination, a concussion within the past year, or at least two previous concussions. New symptoms upon return to play also require this consultation. The Quebec joint guidelines specify these conditions.

Returning to Work or School

Your physical therapist, often in collaboration with your doctor, also plans your gradual return to work or school as soon as it becomes possible. They can advise you on the necessary accommodations:

• Limiting the amount of homework and exams at school
• Managing the amount of time spent in front of screens
• Restricting the amount of physical exertion at work

Returning to school may involve modified exams, breaks, extra time for assignments, or a temporary reduction in the workload. The goal is to resume learning and school life without a significant or prolonged increase in symptoms. These accommodations are gradually reduced as tolerance improves.

What are the symptoms that persist after a concussion?

Persistent symptoms following a concussion are those that last longer than four weeks. This definition applies to children, adolescents, and adults according to the international consensus.¹ A 2021 clinical review also uses this criterion for adults.^[27] A more recent review notes that up to 30% of adults may develop persistent symptoms, depending on the populations studied.^[22] A new assessment identifies issues that need to be addressed and factors that may complicate recovery.

Why do symptoms persist?

Several factors can explain why symptoms persist:

Vestibular problem: A disorder of the inner ear or its connections to the brain can contribute to dizziness and balance problems.

Untreated neck injury: The neck may continue to contribute to headaches and dizziness.

Eye movement problems: Difficulty with convergence or visual tracking can make reading and certain activities more challenging.

Autonomic dysfunction: The system that automatically regulates the heart and breathing (the autonomic nervous system) may become temporarily disrupted, making it harder to tolerate physical exertion⁵. A review summarizing 17 studies supports this hypothesis as an explanation for part of the exercise intolerance, but methods vary widely from one study to another, and the exact mechanism remains to be clarified^[30]. Among other findings, a higher heart rate and reduced heart rate variability—that is, less variation in the time between heartbeats—are observed during light exercise for up to about ten days after the injury, with conflicting results at rest^[31].

Psychological factors: Anxiety, depression, and post-traumatic stress can exacerbate and perpetuate symptoms.

Symptoms That May Persist After a Concussion

• Persistent headaches
• Chronic Fatigue
• Difficulty concentrating
• Memory problems
• Irritability and mood changes
• Sleep Disorders
• Sensitivity to light and noise
• Dizziness

Options When Symptoms Persist After a Concussion

An assessment of symptoms that persist after a concussion identifies relevant factors and allows for a discussion of options as needed.

Specialized physical therapy: treatment for balance, eye movement, and neck problems identified during the evaluation.

Adapted endurance exercise: a progressive program in which the duration and intensity are tailored to the individual’s tolerance for symptoms, as determined in consultation with a healthcare professional.

Psychological support: Therapy can help manage anxiety, stress reactions, and difficulties adapting.

Medical management: medications for headaches or other specific symptoms, as needed.

Improvement is still possible with a plan tailored to the specific problems identified. Options include education, graded exercise, balance exercises, neck therapy, psychological support, and coordinated care among professionals. The 2021 review issued weak recommendations due to low confidence in the available studies.^[27] More recent findings on certain interventions, such as the visual program described above, round out this picture. Each treatment should be selected based on your specific condition and reevaluated according to your progress.

When should you see a doctor, and what are the warning signs?

A suspected concussion requires prompt evaluation; certain symptoms warrant an immediate visit to the emergency room. These symptoms include severe or worsening headaches, repeated vomiting, weakness, or difficulty staying awake. A visit to the emergency room allows for an assessment of other possible injuries and provides appropriate guidance.

Good Reasons to Seek Prompt Consultation

Seek medical attention promptly after a blow to the head, neck, or body if you have symptoms that suggest a concussion. Also seek medical attention if your symptoms are limiting your activities, if you’ve had a concussion before, or before resuming a high-risk sport. A follow-up evaluation is recommended if your condition does not improve after two weeks, if symptoms persist after one month, or if you’re having difficulty making progress.

Warning Signs: When to Go to the Emergency Room

After an impact, the following signs may indicate a more serious injury. Even one of these signs is reason enough to seek immediate evaluation in the emergency room. Call 911 if the person is difficult to wake, is having seizures, or is showing significant deterioration. These signs do not allow you to make a diagnosis on your own.

New double vision, vision loss, or new difficulty walking after the impact also require urgent evaluation. The INESSS guide details the signs to watch for. Signs of these conditions require immediate medical evaluation; if in doubt, seek medical attention.

Who to consult?

Physical therapist trained in concussion care: Can assess and treat concussions, vestibular and cervical issues, and oversee your return to activities. In Quebec, you can see a physical therapist without a referral.

Physician or IPS: Can make a diagnosis, prescribe medication as needed, and refer you to specialists. An IPS is a specialized nurse practitioner.

Neuropsychologist: Can conduct a detailed assessment of memory, attention, and other cognitive abilities when difficulties persist.

What are some common questions about concussions?

Frequently asked questions about concussions include loss of consciousness, recovery times, helmets, screens, rest, returning to sports, repeated concussions, and physical therapy. A concussion can occur without loss of consciousness and requires a gradual return to activities. Helmets reduce certain injuries without eliminating concussions, and physical therapy can address specific issues identified during evaluation. The answers below provide details on recovery times and precautions.

Is it necessary to lose consciousness to have a concussion?

No. The vast majority of concussions occur without loss of consciousness⁶. In a cohort study involving seven high school and college sports, loss of consciousness occurred in 9% of concussions^[18]. The presence of even a single symptom after an impact is sufficient to raise suspicion of a concussion.

How long does a concussion last?

According to the INESSS guidelines, symptoms usually subside within the first two weeks and disappear within a month for most people. Some people recover more slowly. See a doctor if your symptoms do not improve, persist after four weeks, or prevent you from resuming your normal activities. Returning to sports also depends on the stages you have completed and the results of your evaluation.

Do helmets protect against concussions?

A helmet significantly reduces the risk of serious head injuries, such as a skull fracture. However, it does not protect the brain from sudden acceleration, so it does not guarantee that a concussion will be avoided. The protection against serious head injuries is well established for cyclists: among cyclists who have fallen or been struck, helmet use is associated with fewer head injuries, fewer serious injuries, and fewer deaths^[32]. When it comes to concussions, however, the situation is different: in randomized trials conducted in soccer and rugby, helmets did not reduce the number of concussions^[33]. The effect therefore depends on the sport and the type of protective gear. A properly fitted helmet remains important for preventing serious injuries. It is not a substitute for the rules of the game and measures designed to prevent impacts.

Can I look at screens after a concussion?

Limit screen time during the first 24 to 48 hours. After this period, you can use screens if it doesn't significantly worsen your symptoms. Start with short periods and gradually increase your usage.

Should I stay in the dark?

No. After a short period of relative rest, gradually resume your activities as your body allows.

When can I return to sports?

Light physical activity may be resumed during periods of relative rest, depending on tolerance.¹ The initial stages follow the guideline of a slight and brief increase in symptoms. Before Stage 4 and any activity carrying a risk of a blow to the head, clinical recovery and professional clearance are required. The INESSS guidelines also require a full resumption of intellectual activities, without any modifications, before Stage 4. The protocol detailed above explains this progression.

Is a second concussion more serious?

A second concussion may make recovery more difficult, but the course of recovery must be assessed on a case-by-case basis. The brain may also be more vulnerable to another injury during recovery.^[14] A history of concussions increases the risk of sustaining another concussion in sports studies.^[18] In Quebec, a concussion in the previous year or at least two prior concussions requires a new evaluation by a physician or a sports medicine specialist before a decision can be made regarding a return to high-risk activities.

Can physiotherapy really help?

Yes, it can help. In people whose symptoms persisted, a trial showed that neck and balance therapy helped them get clearance to return to sports sooner⁹. The evaluation helps identify the specific issue in your case: balance, eye control, or neck issues.

Do helmets and mouthguards prevent concussions?

Helmets reduce the risk of certain serious head injuries, and mouthguards can reduce the frequency of concussions in certain contact sports. Neither of these pieces of equipment eliminates the risk. Their effectiveness depends on the sport, the type of protection, and how it is used.

The helmet

A helmet does not eliminate the risk of a concussion. Its protective effect varies depending on the sport, the type of helmet, and how well it fits, but it remains important for reducing head and facial injuries.

Feeling protected by a helmet can make you want to play harder. A helmet doesn't make blows to the head harmless: using it as an excuse to charge headlong into things is still a bad idea.

Mouthguards

A mouthguard reduces injuries to the mouth and teeth. Choosing the right one and ensuring it fits properly are important; ask for advice on a model suited to your sport. Regarding concussions, a meta-analysis of five cohorts published in 2019 did not reach a conclusive finding.^[34] A 2023 review found a concussion rate approximately 26% lower among mouthguard wearers in the contact sports studied.^[35] This rate compares the frequency of concussions during sports participation; it does not mean that all individuals or all models provide the same level of protection. To separate fact from fiction regarding prevention, read “Myths and Facts About Concussions.”

What related issues should be investigated after a concussion?

Conditions to investigate after a concussion include whiplash, neck pain, headaches, and dizziness. The same impact can affect both the head and the neck. An evaluation helps distinguish between their respective contributions.

Resources on Related Issues

The following resources explain the injuries and symptoms that may accompany a concussion.

• Whiplash: It can occur along with a concussion, because the same impact affects both the head and the neck.
• Neck Pain: A Comprehensive Guide —The neck can contribute to symptoms that persist after a concussion.
• Physical Therapy for Neck Pain: Treatments for Neck Problems
• Headaches: a common symptom after a concussion
• Dizziness and lightheadedness: if you have vestibular problems
• Whiplash: a common cervical injury that occurs when a concussion results from a traffic accident

What should you know about concussions?

A concussion disrupts brain function and requires a gradual return to activities that is tailored to the symptoms and the evaluation. Normal imaging results do not rule out this injury.

Key takeaways

Recovery varies from person to person. Prolonged complete rest is no longer recommended. Appropriate exercise and targeted care can help you resume your activities. Physical therapy focuses in particular on balance, eye movements, and neck mobility. Seek medical attention promptly after a suspicious impact and immediately if you notice any warning signs.

How do I make an appointment with a physical therapist?

You can schedule an appointment at Physioactif directly, without a doctor’s referral. Our physical therapists trained in concussion care can assess your symptoms, recommend appropriate treatment, and guide you through your return to normal activities. If you suspect a serious injury or notice any warning signs, seek emergency care rather than making a clinic appointment.

References

1. Patricios JS, Schneider KJ, Dvorak J, et al. Consensus statement on concussion in sport: the 6th International Conference on Concussion in Sport—Amsterdam, October 2022. British Journal of Sports Medicine. 2023;57(11):695-711. PubMed
2. Schneider KJ, Leddy JJ, Guskiewicz KM, et al. Rest and treatment/rehabilitation following sport-related concussion: a systematic review. British Journal of Sports Medicine. 2017;51(12):930-934. PubMed
3. Leddy JJ, Haider MN, Ellis MJ, Willer BS. Exercise is medicine for concussion. Current Sports Medicine Reports. 2018;17(8):262-270. PubMed
4. Reneker JC, Clay Moughiman M, Cook CE. The diagnostic utility of clinical tests for differentiating between cervicogenic and other causes of dizziness following a sports-related concussion: An international Delphi study. Journal of Science and Medicine in Sport. 2015;18(4):366-372. PubMed
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