When you hit your head, fall or get tackled to the ground, your brain can bounce and move against the skull’s bony structure. This results in a concussion or a mild traumatic brain injury (TBI) and brings symptoms of varying severity.

Some events that cause concussions include falls, car accidents and physical assaults, but athletes involved in contact sports are also vulnerable to TBIs. In fact, at least 1.6 million sports-related concussions are estimated each year in the United States.  

Mild concussions may cause short-term symptoms that typically resolve within a week or two, but some patients experience symptoms that linger longer, even with time and rest. 

Moreover, athletes engaged in contact sports like soccer, rugby, ice hockey and boxing are at risk of repetitive concussions and their long-term consequences. At what point do multiple TBIs become problematic? How many concussions are too many? Let’s dig deeper into these fundamental topics on concussions in the following sections. 

How Many Concussions Can You Have? 

If you are an athlete or a parent of an athlete, you may have heard of the three-strike rule. This was developed 60 years ago and essentially said that an athlete who has suffered three concussions in a season will have to sit out for the rest of that season. However, this rule is not based on scientific data.

Rather than the number, more relevant factors to consider when an athlete should stop or return to the game include the severity and recentness of the last concussion. Suffering three TBIs in a single year differs from suffering the same number of concussions over three years. 

An individual’s response to brain injuries also influences how many concussions are too many for that person. For example, those predisposed to certain problems can experience worsened dizziness or balance issues after a single head injury. 

How Many Concussions Are Too Many for an Active Athlete? 

As every person is different, there’s no definite number of how many head injuries a person can sustain before permanent damage occurs. After all, some experience long-term complications after a single concussion, while others seem fine after multiple injuries. Still, the more traumas you’ve had, the greater the chances of permanent damage. 

It’s also worth stressing that how many concussions you can have isn’t the best question to ask, as it encourages an unhealthy understanding of how TBIs can cause damage. Following the three-concussion rule or setting a specific limit can discourage athletes from reporting symptoms so that they can continue playing. 

As individuals experience head injuries differently, discussing your vulnerability and injury history is a better approach. The timing between the injuries matters as athletes who continue to play with a healing concussion can develop worse symptoms, double their recovery time and suffer more significant impairment. There’s also the risk of suffering second impact syndrome, which happens when an already-damaged brain swells up rapidly after getting hit again. 

The Second Impact Syndrome 

This is a rare but potentially fatal phenomenon in individuals sustaining a TBI while recovering from a recent concussion. Also known as repetitive head injury syndrome, this is when the brain dramatically swells after a second concussion before symptoms from an earlier injury have resolved. 

Second-impact syndromes are often fatal, and the few who survive usually become severely disabled. 

Common Short-Term and Long-Term Symptoms of Concussion

Athletes and non-athletes who suffered a blow to the head may experience physical, emotional and psychological symptoms. They may experience a headache, nausea or vomiting, double vision, confusion, fatigue or sensitivity to light, among many others. Other symptoms include losing consciousness or not recalling getting injured. Some also report feeling sluggish or hazy. 

Meanwhile, persistent symptoms post-concussion include but are not limited to irritability, loss of concentration and memory, sleep disturbances, smell and taste dysfunction and anxiety. 

Consequences of Repetitive Head Impacts and Multiple Concussions 

The recovery time for a single concussion is typically short. Symptoms usually disappear within ten days, but they can also last up to three months in some cases. Fortunately, once they are resolved and the brain has healed, there are usually no further complications. 

However, it’s a different story when there are multiple concussions involved. The brain needs time to recover from an injury, so permanent damage can happen when it is overwhelmed by several injuries. 

After too much trauma, blood flow and oxygenation in the brain are negatively impacted. This makes it hard for the brain cells to do their job, consequently hampering an individual’s ability to think, concentrate and even move. Ultimately, repetitive brain injuries can lead to chronic traumatic encephalopathy, a progressive degenerative disease. 

Repeat injuries while recovering from a recent concussion can cause life-changing consequences. However, it’s important to note that it can also occur with less force, as the brain is at an increased risk while still healing. 

Findings from Sports Studies 

In boxing, attacking the head and face of the opponent is part of the game. While amateur boxers wear protective gear, the nature of the sport makes concussions and even severe brain injuries common among fighters. 

A 1997 study examined boxers who played 12 or more professional bouts and, therefore, had higher exposure to head contact and compared their neurocognitive performance with those who played less than 12 professional bouts. The authors reported that the first group had lower cognitive function than the latter. 

A high-resolution MRI study of 100 professional boxers in 2009 also showed a significant correlation between their years in the sport and diffuse axonal injury. It is a type of traumatic brain injury that occurs when axons in the brain become torn as the brain rapidly moves and rotates inside the skull. This movement typically results in the shearing of nerve fibers and usually leads to a coma. 

Considering all these, it’s best to move beyond asking how many concussions are too many for an individual. Whether in a boxing ring or field, it’s best to sit out if you’re at risk for a repeat injury until you’ve healed. The brain is vulnerable after a trauma, and successive injuries will only increase the chances of permanent deficits.  

When To Return to a Sport 

Just like, “How many concussions can you have?” it’s difficult to give a definite answer for when it’s best for an individual to return to a sport. Return-to-play guidelines vary by the severity of the head injury. 

With that said, the Centers for Disease Control and Prevention recommends a graduated return-to-play protocol for players who suffer concussion symptoms like confusion or loss of consciousness. Following these six gradual steps is a great starting point, but working closely with your physician is still paramount. Athletes who continue to play sports after concussions risk repeat injuries, more serious complications and a longer recovery time. 

Managing Concussion Symptoms and Recovering from Traumatic Brain Injury 

Most sports-related concussion symptoms resolve on their own within two weeks. Athletes can also return to their sports practices if they have the approval and supervision of their healthcare provider. 

However, in cases where multiple or severe concussions resulted in mobility issues, speech and language impairment, or emotional and behavioral struggles, undergoing rehab is recommended. Rehabilitation programs can take many forms, including physical, occupational, speech and language therapy, as well as counseling and community integration. These are designed to help patients recover from the effects of their injury. 

Ultimately, a proactive approach is the key to a speedy and successful recovery. Simply mitigating the symptoms with medication may increase your comfort, but it doesn’t address the underlying issue.  

Start Your Recovery Journey with Moody Neurorehabilitation

At Moody Neurorehabilitation, we’re all about empowering patients to gain independence and return to the activities they love. With our world-class facilities, experienced staff and passion for improving the lives of our patients, we provide highly personalized care for adolescents and adults with acquired brain injury. 

We serve several locations across Texas and are available to begin the admissions process for you. Upon admission, a comprehensive evaluation will be done to develop a rehabilitation regimen tailored to your cognitive and emotional status. Please don’t hesitate to contact us to schedule a tour or refer a patient.  


Moody Neurorehabilitation Institute (Moody Neuro) provides personalized care to treat the unique challenges of brain injury with the singular purpose of achieving the best possible outcome for patients and their families.


Similar Articles

The Top 10 Traumatic Brain Injury Books to Read

Books can be an invaluable resource for traumatic brain injury (TBI) survivors, their loved ones, and their caregivers who want to learn more about this condition. There are many traumatic brain injury books that are helpful for anyone...

Being Kind to Ourselves Makes a Difference

We each tend to be our own harshest critic. There is nothing that someone can say that would be meaner or nastier than what we say to ourselves. This is a natural part of being human; everyone does...

What is a Non-Traumatic Brain Injury?

A non-traumatic brain injury (nTBI) refers to brain damage caused by factors other than external trauma. These causes can include exposure to certain toxins, complications of an infection, or a symptom of a medical condition. A stroke is usually the...
© 2023 Moody Neurorehabilitation Institute
Back to Top