Is rest really best?
The new evidence on exercise after concussion
If you’ve ever had a concussion and been given advice on what to do after, it’s likely you were told to rest. No work, no school and definitely no contact sports. You may have even been told to stay in bed, in a dark room, for days on end. But what if I told you that perhaps the (albeit well-intentioned) advice on rest was actually prolonging your recovery and making you feel worse.
New evidence on exercise after concussion injuries suggests just that.
Recent studies have found that exercise may play an important role in the recovery of acute concussion and in prevention of the development of prolonged concussion symptoms (PCS).
Let’s examine why rest was considered for years to be the gold standard “treatment” after sustaining a concussion.
Firstly, it is understood that concussion injuries create a temporary energy deficit in the brain. Therefore, any activity that burns energy (physical or cognitive) could theoretically compound this effect and make the concussion worse. Early research on animals supported this idea; activity too early after sustaining a concussion injury was associated with a reduction of energy and important healing compounds in the brain (ie: BDNF). The recommendation became to rest. This would conserve energy and help heal the injured brain.
Makes sense, right?
Secondly, rest also helps to reduce the chance of sustaining another concussion during recovery, which could result in a more severe and potentially permanent brain injury known as Second Impact Syndrome. For these two reasons, rest, for many years seemed like a logical thing to do following a concussion. However, emerging evidence on exercise is challenging this long-held belief and setting the stage for some new recommendations following concussion.
One of the first studies to examine the effects of exercise on concussion recovery came from a group in Buffalo. Dr. John Leddy and colleagues found that 70% of PCS patients that underwent a specific exercise protocol achieved full recovery, compared to only 20% in the group that did not exercise(1). Thankfully, researchers in Buffalo continued exploring these results – they thought, if it works in people who are already chronic, maybe it can help prevent people from becoming chronic in the first place. Since then, this group has published more than 10 different studies demonstrating the beneficial effects of exercise on concussion recovery.
Ann Grool and colleagues published one of the largest studies on pediatric concussions and found that people who engaged in physical activity within the first week after injury were significantly less likely to suffer from symptoms beyond 4 weeks(2). More recently, researchers from the University of Toronto found that each successive day that a patient waited to initiate exercise, resulted in a more prolonged recovery. In other words, if you started light exercise 1 day after injury, it was better than if you started on day 2. Starting on day 2 was better than day 3, and so on(3). In fact, kids in this study actually returned to school faster if they exercised earlier! (Note: there are limitations to both of these studies and we don’t yet advocate vigorous exercise early in the recovery process, but the bulk of the evidence at this point does suggest that very LIGHT exercise (i.e., going on walks, light stationary bike) is safe and may speed recovery).
In 2019 the first ever randomized clinical trial was completed in Buffalo with acute patients (average time was 4 days after injury). All patients demonstrated an intolerance to exercise during treadmill testing. Half the group was put in the exercise group, and half was put in a placebo group. Those in the exercise group recovered significantly faster than those in the placebo group(4). This is why now, at all Complete Concussion Management locations, we provide treadmill testing as early as 5 days after injury – to establish a safe exercise level and help to speed recovery of our concussion patients. (click here to find a clinic near you for this testing)
Not only may exercise be beneficial to concussion recovery, but recent research has also found that too much REST may actually be detrimental. One study showed that adolescents who rested for 1-2 days and then gradually returned to activity recovered faster than ones that were told to strictly rest for 5 days(5). A 2015 study found that patients who adhered to their doctor’s advice surrounding strict rest did worse compared to those that did not listen to advice to rest(6). And a 2019 study by Noah Silverberg titled “Advice to rest for more than 2 days after mTBI (concussion), is associated with delated return to productivity” concluded “this study supports growing evidence that prolonged rest after concussion is generally unhelpful” (7). One possible reason as to why this may happen is due to the “nocebo effect”, which is the creation of illness based on the expectation of illness. Another idea is that the advice to strictly rest “medicalizes” the patient’s condition and creates intense worry surrounding the implied severity of the injury. The symptoms of the psychological distress that results are often the same as the concussion injury itself. Other potential negative effects of strict rest include physical deconditioning, impairment of blood flow and an increase in anxiety and depressive mood symptoms.
Although more research is needed regarding the specific guidelines surrounding exercise post-concussion, the early studies are encouraging. Current best practices encourage 1-2 days of light activity that does not provoke symptoms, followed by a gradual reintroduction of activities such as school and work. This should always be coordinated by a healthcare professional with training and experience in concussion – find one here.
- Baker JG, Freitas MS, Leddy JJ, Kozlowski KF, Willer BS. Return to full functioning after graded exercise assessment and progressive exercise treatment of postconcussion syndrome. Rehabilitation Research and Practice. Hindawi; 2012;2012(2):705309–7.
- Grool AM, Aglipay M, Momoli F, Meehan WP III, Freedman SB, Yeates KO, et al. Association Between Early Participation in Physical Activity Following Acute Concussion and Persistent Postconcussive Symptoms in Children and Adolescents. JAMA. 2016 Dec 20;316(23):2504.
- Lawrence DW, Richards D, Comper P, Hutchison MG. Earlier time to aerobic exercise is associated with faster recovery following acute sport concussion. Janigro D, editor. PLoS ONE. 2018 Apr 18;13(4):e0196062.
- Leddy JJ, Haider MN, Ellis MJ, Mannix R, Darling SR, Freitas MS, et al. Early Subthreshold Aerobic Exercise for Sport-Related Concussion. JAMA Pediatr. 2019 Feb 4;:1–7.
- Thomas DG, Apps JN, Hoffmann RG, McCrea M, Hammeke T. Benefits of Strict Rest After Acute Concussion: A Randomized Controlled Trial. PEDIATRICS. 2015 Feb 2;135(2):213–23.
- Moor HM, Eisenhauer RC, Killian KD, Proudfoot N, Henriques AA, Congeni JA, et al. The relationship between adherence behaviors and recovery time in adolescents after a sports-related concussion: an observational study. Int J Sports Phys Ther. 2015 Apr;10(2):225–33.
- Silverberg ND, Otamendi T. Advice to Rest for More Than 2 Days After Mild Traumatic Brain Injury Is Associated With Delayed Return to Productivity: A Case-Control Study. Front Neurol. 2019 Apr 12;10:6–6.