Updated: Oct 2, 2021
Most consensus and agreement statements for managing concussions in sport recommend that athletes rest completely, both physically and cognitively, until they become symptom-free. Prescribed total rest for sports related concussion is one of the most widely used recommendation for the treatment of the school age athlete, with no physical activity mandated until completely asymptomatic for one week.
To date there is insufficient evidence that prescribing complete rest promotes recovery or eases symptoms. Anecdotally, it appears not allowing an athlete to return to school and not allowing them to exercise, may lead to worsening of symptoms and even more depressive symptoms.
A recent randomized clinical control study in JAMA Pediatrics found adolescent athletes who sustained concussions who underwent a supervised aerobic regimen recovered more quickly than those allowed to only stretch.
After a brief period of rest of 1 to 2 days after sustaining a concussion, with no worrisome or significant signs or symptoms, concussed athletes should be encouraged to gradually and progressively increase activity while staying below their cognitive and physical symptom-exacerbation threshold; that is allow to participate in cognitive and light aerobic activity that does not bring on or worsen their symptoms. Stationary bicycle, treadmill walking, or outdoor walking can be initiated to start. Lifting heavy weights while bearing down (valsava) should be avoided, as should extreme motion and movement activity.
To determine exercise intensity each athlete could sustain without worsening symptoms, the researchers in the study had each athlete undergo the Buffalo Concussion Treadmill Test, to determine at what level their symptoms worsen. As the patient walked on a treadmill, the incline was gradually
increased and the heart rate was recorded at the point where concussion symptoms intensify. Exercise was prescribed at 80% of that heart rate threshold. A word of caution is that in my experience, many athletes can't determine that threshold as symptoms may worsen post exercise, so make sure your athletes start real easy making sure they are listening to their mind and body.
References: John J. Leddy, Mohammad N. Haider, Michael J. Ellis, Rebekah Mannix, Scott R. Darling, Michael S. Freitas, Heidi N. Suffoletto, Jeff Leiter, Dean M. Cordingley, Barry Willer. Early Subthreshold Aerobic Exercise for Sport-Related Concussion. JAMA Pediatrics, 2019.