Should You Rest After a Concussion?

Research-informed explainer — last updated April 12, 2026

For decades, the standard advice after a concussion was simple: rest completely until all symptoms are gone. No exercise. No screens. No school. No activity that makes your head hurt. New research has overturned that guidance — and the reversal is not subtle. Evidence now shows that prolonged rest actually delays recovery, while supervised aerobic exercise starting as early as 24 to 48 hours after injury produces meaningfully faster healing.

This explainer draws on research from three sports medicine physicians in the Convene directory. John Leddy at the University at Buffalo is the researcher most responsible for changing how concussion recovery is managed — his randomized controlled trial published in JAMA Pediatrics established the clinical foundation for early aerobic exercise protocols. Damond Blueitt contributed research on vestibular and ocular motor screening as a predictor of recovery time in youth athletes. Sara Gould has studied vision and academic symptoms in children with concussion, which informs how clinicians screen for the subgroup of patients who need a more cautious approach.

What was the old guidance, and why did it seem logical?

Until roughly the mid-2010s, the consensus was "cocoon therapy" — keeping concussed patients in a dark, quiet room with no physical or cognitive exertion until symptoms fully resolved. The reasoning was intuitive: the brain was injured, rest would let it heal, and any activity that provoked symptoms would set recovery back.

That logic would be correct if concussion were primarily a structural injury — a bruise on the brain that needed time to mend. But that is not the dominant mechanism in most uncomplicated concussions. The physiological basis is different, and understanding why changes everything about how recovery should be managed.

Why rest is not the answer: the physiology of concussion

Concussion produces disruption to the autonomic nervous system — the system that regulates heart rate, blood pressure, breathing, and blood flow throughout the body, including to the brain. Research from John Leddy's group has shown that concussed patients often develop exercise intolerance: they reach their symptom threshold at abnormally low exercise intensities, accompanied by inappropriate ventilation and elevated carbon dioxide levels in the blood [4].

That elevated carbon dioxide increases cerebral blood flow out of proportion to what the brain needs at that exertion level, which is associated with symptom flare-ups. The key insight is that this dysregulation of the autonomic nervous system — not tissue damage — is what prolongs recovery in most concussion patients. And the autonomic nervous system responds to exercise.

Prolonged rest does not address ANS dysfunction. In fact, it may reinforce it. Patients who rest for weeks become deconditioned, anxious about physical activity, and stuck in a feedback loop where any exertion triggers symptoms — not because the brain is still injured, but because the body has become sensitized to the avoidance itself.

What Leddy's research actually showed

The landmark study was a randomized controlled trial published in JAMA Pediatrics in 2019 [2]. Leddy and colleagues enrolled adolescents aged 13 to 18 who had been diagnosed with a sport-related concussion within 10 days of injury. Participants were randomly assigned to either a subsymptom threshold aerobic exercise program or a placebo program of light stretching.

The aerobic exercise group recovered significantly faster — their median time to full recovery was 13 days, compared to 17 days in the stretching group. The exercise group also had a lower rate of delayed recovery (symptoms persisting beyond four weeks): 10% versus 40% in the stretching group.

This was not a marginal difference. Early supervised aerobic exercise cut the rate of prolonged recovery by 75% relative to the placebo condition. The trial, combined with a 2017 systematic review published in the British Journal of Sports Medicine [3], helped establish the consensus: there is no evidence that rest beyond the first 24 to 48 hours accelerates concussion recovery, and there is good evidence that aerobic exercise does.

The subsymptom threshold protocol — what it means in practice

"Subsymptom threshold exercise" means exercising at a level that does not provoke your symptoms. You are not pushing through headache or dizziness. You are finding the intensity just below the point where symptoms emerge — and staying there, then incrementally raising that threshold over successive sessions as your brain and autonomic system recover.

The Buffalo Concussion Treadmill Test (BCTT) is the clinical tool for identifying that threshold. Developed by Leddy and colleagues, the test uses a standardized incremental treadmill protocol to find the heart rate at which an athlete's symptoms are provoked. That symptomatic heart rate, minus about 20 beats per minute, becomes the target heart rate for their exercise prescription [4].

In practice this might look like 20 minutes of brisk walking, light stationary cycling, or swimming — not contact sports, not weight training, not anything that risks another head impact. The goal is physiological rehabilitation of the ANS, not cardiovascular fitness.

What vestibular and ocular motor screening adds

Not all concussion symptoms are driven by ANS dysfunction. A subset of patients — particularly younger athletes — have significant vestibular and visual system involvement: problems with balance, gaze stability, convergence, and the coordination between eye movements and head movements.

Research from Damond Blueitt and colleagues, published in The American Journal of Sports Medicine in 2016, found that a positive result on the Vestibular/Ocular Motor Screening (VOMS) assessment — meaning the patient had symptom provocation or abnormality on any of the vestibular or visual domains — was associated with significantly longer recovery time after sport-related concussion in youth and adolescent athletes [6].

The VOMS test takes about five minutes and screens five domains: smooth pursuit, saccades, near point of convergence, vestibulo-ocular reflex, and visual motion sensitivity. Patients who screen positive on the VOMS often benefit from vestibular rehabilitation therapy in addition to — or prior to — the aerobic exercise program. Sara Gould's work on vision symptoms and academic difficulty in concussed children reinforces that visual and vestibular problems have real downstream effects on school performance, and that these domains need to be assessed, not just tracked passively [5].

Who this applies to — and who needs more caution

The research on early aerobic exercise applies specifically to uncomplicated sport-related concussion. Before beginning any exercise program after a head injury, structural injury must be ruled out.

Red flags that warrant urgent imaging and more conservative management include: loss of consciousness longer than a minute, a seizure at the time of injury, worsening headache that doesn't respond to over-the-counter pain relief, repeated vomiting, progressive cognitive deterioration, or focal neurological signs like weakness in one limb or slurred speech. These findings need CT or MRI to rule out intracranial bleeding — hemorrhage or a subdural hematoma cannot be treated with a treadmill test.

For the majority of concussions that are uncomplicated — which is most sport-related concussions in otherwise healthy athletes — the concern is not structural damage but physiological dysregulation, and early graded exercise is the appropriate treatment.

Patients with significant vestibular involvement, persistent VOMS abnormalities, or anxiety-driven avoidance behavior may benefit from a supervised multidisciplinary approach that includes vestibular therapy and sometimes behavioral support in addition to aerobic exercise.

Questions to ask your sports medicine doctor

• Is there any reason I need imaging before starting exercise, or does my presentation suggest an uncomplicated concussion?
• When can I start light aerobic activity — is it appropriate to begin within the first 48 hours?
• Should I have a Buffalo Concussion Treadmill Test to identify my safe exercise threshold before I start?
• Do my symptoms suggest vestibular or visual system involvement that would change my rehab approach?
• What heart rate should I stay below during exercise, and how do we progress from there?
• What symptoms during exercise should prompt me to stop, and what symptoms should prompt me to call you?

The bottom line

For uncomplicated sport-related concussion without evidence of structural injury, the research is now clear: complete rest beyond the first 24 to 48 hours is not the right approach, and it can meaningfully delay recovery. Early supervised aerobic exercise at a subsymptom threshold — starting from roughly Day 2 or 3 after injury — outperforms rest in randomized controlled trials. The biological reason is that concussion disrupts the autonomic nervous system, not just brain tissue, and the ANS responds to graded physical challenge.

The Buffalo Concussion Treadmill Test identifies each patient's individual exercise threshold. For patients with vestibular or visual symptoms, VOMS screening adds important information and may indicate a need for targeted vestibular rehabilitation. In either case, the direction of travel is the same: earlier, calibrated activity — not prolonged stillness — is how the brain recovers.