A concussion is a mild traumatic brain injury that occurs when a blow to the head or a sudden jolt causes the brain to move rapidly within the skull. This movement can stretch and damage brain cells, leading to temporary changes in brain function. While concussions are often not life-threatening, their effects can be significant and last for days, weeks, or even longer. Engaging in strenuous physical activity, such as running, is generally not recommended after a concussion, as it can hinder the brain’s recovery process. Prioritizing brain rest and avoiding activities that could worsen the injury is important for healing.
Why Exertion Worsens Concussion Recovery
Physical exertion, particularly running, negatively affects a healing brain due to several physiological changes initiated by a concussion. Immediately following a concussion, the brain enters a state often referred to as an “energy crisis”. This occurs because the initial injury triggers a sudden, high demand for energy. However, this increased energy demand happens at a time when the brain’s ability to produce energy is impaired, creating a mismatch between supply and demand.
During physical activity like running, the heart rate and blood flow increase significantly. For a concussed brain already struggling with an energy deficit, this increased demand can further deplete its strained energy resources. The brain’s regulatory mechanisms, which control blood flow, may also be disrupted after a concussion, leading to an imbalance that can exacerbate symptoms or prolong recovery. This can worsen existing symptoms such as headaches, dizziness, and nausea.
Returning to activity too soon also carries the risk of Second Impact Syndrome (SIS), a rare but severe condition. SIS can occur if a person sustains a second head injury before fully recovering from an initial concussion. Even a seemingly mild second impact can lead to rapid and severe brain swelling, which can result in long-term disability or even be fatal. This heightened vulnerability underscores the need for sufficient healing time before resuming physical activities.
Identifying Concussion Symptoms
Recognizing the signs and symptoms of a concussion is important for timely intervention and proper management. Concussion symptoms can vary widely among individuals and may appear immediately after the injury, or they might be delayed for hours or even days. Some people may not notice symptoms until 24 to 48 hours later, or sometimes up to 72 hours.
Symptoms are broadly categorized and can affect various aspects of a person’s well-being. Physical symptoms include headaches, a feeling of pressure in the head, dizziness, balance problems, nausea, vomiting, blurred vision, and sensitivity to light or noise. Cognitive symptoms involve difficulties with thinking, such as trouble concentrating, memory issues, feeling “foggy,” and slowed reaction times.
Emotional changes can also manifest, including irritability, mood swings, anxiety, and sadness. Sleep-related symptoms might include insomnia, sleeping more or less than usual, or trouble falling asleep. Even minor impacts can cause a concussion, and the absence of unconsciousness does not rule one out. Seeking medical evaluation from a healthcare professional is important for accurate diagnosis and guidance.
Safe Return to Activity Guidelines
Returning to physical activity, including running, after a concussion requires a structured and gradual approach, often called a graduated return-to-activity protocol. This process helps ensure the brain has adequately recovered and can tolerate increasing levels of exertion without a return of symptoms. The initial phase of recovery typically involves a short period of relative rest, usually 24 to 48 hours, followed by a gradual reintroduction of light activities.
Progression through the stages depends on remaining symptom-free at each level of activity. For example, initial activities might include light aerobic exercise like walking or stationary cycling at a low intensity. As these are tolerated without symptoms, intensity and duration can be slowly increased. If any concussion symptoms reappear or intensify during an activity, the person should revert to the previous symptom-free stage.
Medical clearance from a healthcare provider or a concussion specialist is important before and throughout this return-to-activity process. They can assess recovery and provide specific guidance tailored to the individual’s progress. The timeline for full return to running varies significantly, often taking several weeks, and should not be rushed. Patience and listening to the body’s signals help prevent setbacks and support a complete recovery.