Many moons ago (circa 2009-2010) I was a sports sciences resident, eager to learn anything and everything sports injury related on route to becoming a sports Chiropractor. Concussions were, and continue to be (for good reason), a major topic of concern in Sports Medicine with lots of academic research being conducted all over the world.

I had read about a novel approach being developed and implemented by a Sports Medicine Doctor at the University of Buffalo named Dr. John Leddy. He was the only person in the concussion world at the time who published research using exercise as an active treatment strategy to treat concussion symptoms from becoming chronic or long lasting. His belief was that in a large number of concussion cases basic physiological processes like regulating heart rate, blood pressure and cerebral blood flow for example became dysfunctional and that aerobic exercise could be the solution to these disturbances.

I reached out to Dr. Leddy in 2010 to request to observe him in his clinic because I was hoping to see how he implemented this treatment strategy in his own practice. And what I observed that day, changed my entire perspective on concussion management. Dr. Leddy had a structured approach to categorizing each concussion case he saw based on the treatment approaches they might benefit from. Some concussion cases struggled with vision and balance for example and required the help of his vestibular physiotherapy colleagues, some struggled primarily with headaches and neck pain and needed help from his manual therapy (physio, chiro, massage) colleagues and the majority struggled with exertion, being able to get more active again without triggering their symptoms; those patients required what he called a sub-threshold aerobic exercise approach. And for some challenging cases with long lasting symptoms pharmacological approaches were considered as well. It was clear to me that Dr. Leddy was not just hell bent on proving his theory for ‘exercise cures all concussions’, but that saw he the big picture of concussion management through a lens that no one else was looking through.

Dr. Leddy was criticized by colleagues in the concussion world for many years for building a treatment paradigm that countered the mainstream narrative at the time which was more of a rest, watch and wait approach. The prevailing thought was that progressive return to work and activity started when the patients symptoms subsided. Wait until the condition gets better and then start treatment…seems almost laughable in retrospect doesn’t it? (Imagine having a shoulder injury and being told to wait for symptoms to get better and then to come back to start rehabilitation?).

A 2021 multicentre randomized trial conducted by Dr. Leddy and colleagues found that early (within the first 10 days) subthreshold daily aerobic exercise for adolescent concussions led to faster recovery and reduced risk for post concussive symptoms compared to stretching.  These are difficult studies to conduct, and data collection was hampered by the pandemic (concussions weren’t happening at the same rates when adolescent activities were on hold). However what this study proved was Dr. Leddy and his team don’t have some sort of magic concussion touch at the University of Buffalo. This is a strategy that can be employed elsewhere and can be started much earlier than he originally tested a decade earlier.

His work has now been accepted as a primary treatment strategy in the 6th concussion consensus statement held by the international conference on concussion in sport.  The concussions consensus group concludes there is strong evidence regarding the benefits of physical activity and aerobic exercise treatment as early interventions.

This is no longer a rogue theory, aerobic exercise (in the right dose at the right time) now shouldn’t just be allowed in some cases as part of concussion recovery it should be prescribed in almost all cases.

We now know that light exercise, including walking or a stationary bike (or other cardio equipment with no risk of falling) should start as early as 24-48 hours post concussion. And the structured sub-threshold exercise approach should start between 2-10 days post concussion.

What is sub-threshold aerobic exercise?

 

In a large portion of concussion cases concussion symptoms are aggravated by exertion. To help identify what that level of exertion is that triggers symptoms, Dr. Leddy developed the Buffalo Concussion Treadmill test to monitor heart rate with a structured progressive increase in exertion.

For a brief summary on the Buffalo Concussion Treadmill Test, check out this article we wrote back in 2016 and it’s corresponding video with almost 10k views!

More recently Dr. Leddy has developed a similar test using a bike instead of a treadmill, to further improve the safety of testing people with concussions which has been shown to be equally capable of identifying the symptom threshold.

The Buffalo Concussion Bike Test uses a similar principle, progressive exertion monitored by heart rate with check points on symptoms scores (using a 10 point Likert scale) and exertion level (Borg scale). The bike test uses a consistent cadence (between 60-70 rpm) and progresses resistance every 2 mins, versus the bike test which progresses speed/incline every minute. For optimal testing a bike that can give the power output in Watts (the combination of cadence and resistance) is preferred. Check out the chart attached developed by Dr. Leddy’s team, which progresses each level on watts based on the participants weight.

We’ve learned so much about concussion diagnosis, assessment and management in the last decade. If you’re interested in more recent developments in sport related concussion research check out a recent podcast from Dr. Peter Attia with guest Dr. Micky Collins from the University of Pittsburgh, whose concussion clinic has published more than 150 academic papers on sport related concussion. Did you know that early symptoms of dizziness or feeling of being in a fog are the symptoms with the longest prognostic recovery time? Or that girls are more vulnerable to concussions than boys (60% vs 40% according to Dr. Collins).

And like Dr. Leddy’s clinic, Dr. Collins believes that treatment needs to start early and be customized with specific exercise approaches utilized for rehabilitation in combination with manual therapy, vestibular therapy, oculomotor therapy and pharmacotherapy as needed.

The advances in the sports concussion world have accelerated at a pace that most busy physicians just couldn’t possibly keep up with and will take years, maybe decades to disseminate down into your local walk-in clinic or emergency room physician. Quite simply, if you are being told to rest, you need to seek alternative advice.

Concussion treatment needs to start early (within days) with experienced clinicians who are able to quarterback the entire treatment process from a structured aerobic exercise plan, manual therapy on the neck and surrounding structures when appropriate and consideration for specific referrals (ie vestibular therapy and oculomotor therapy).