Background Information:

• An estimated 3.8 million people sustain a concussion every year1,4
• 10% – 33% of individuals with mild traumatic brain injury experience symptoms months to years later1
• Post-concussion syndrome (PCS) is defined as persistence of > 3 symptoms 7-10 days after injury5: Headache, Dizziness, Fatigue, Irritability, Insomnia, Concentration Difficulty, Memory Difficulty, Stress or emotion intolerance
• One cause of PCS may be altered autonomic function and impaired autoregulation and distribution of cerebral blood flow

Clinical Case:

• 15 y.o. female student s/p MVA 1 month ago hitting head on dash board
• ER visit diagnosed mTBI –> prescribed “rest”
• S/s:  headaches, fatigue, worsens with reading, noisy family, screen time
• Goals: asymptomatic school day, return to tennis, recreational running
• PT: Vestibular, postural, and cervicogenic exercises initiated

PICO: Is aerobic exercise beneficial in individuals with prolonged symptoms after mTBI?

Search Strategy: 1,247 articles identified in PubMed, CINAHL, Academic Search Complete

• Terms: (concussion OR post-concussion syndrome OR mild traumatic brain injury) AND (exercise OR rehabilitation OR treatment). English language, peer reviewed, humans, 10 years.
• Inclusion: subjects sustained mild TBI/concussion by means of sport, MVA, or other,  experiencing post-concussive symptoms > 2 weeks, exercise intervention defined, post-concussive related outcome measures (symptoms, fatigue, QOL, function)
• Exclusion: acute phase mTBIs, moderate to severe TBI’s, non interventional studies

Results:

^aPost-concussive symptoms > 4 weeks ^aa > 6 weeks, ^bBalke Treadmill test, BDI: Beck Depression Inventory, PCSI: Post Concussion Symptom Inventory, PCS: Post Concussion Scale, SE: statistically significant effects listed (p <0.05)

Limitations and suggestions:

• “Active” control groups1,3, Lack of control group2,3,5
• Small sample size1-5
• Multiple treatment interference2
• Inadequate follow up1-3,5
• Lacking consensus on intensity and duration
• Optimal timing of intervention unclear
• Higher quality research suggested to directly compare aerobic exercise with other interventions such as dual tasking, cervicogenic, vestibular exercises, and non participants.

Clinical Bottom Line:

There is moderate to low level evidence to support the use of aerobic exercise in patients with prolonged symptoms after sustaining a mild traumatic brain injury.  This particular literature review offers recent interventional case studies and a randomized clinical trial in which aerobic exercise is the primary intervention and assessment tool used to prescribe a customized, progressive, aerobic rehabilitation program whether on a treadmill or stationary bike. Each study reported a statistically significant change in some aspects of post-concussive symptoms such as return to full daily functioning, ability to exercise maximally without symptom exacerbation, and decrease in post-concussion symptom specific scales. No adverse events or negative impacts were reported in the studies from engaging sub-symptom exacerbation aerobic exercise in patients still experiencing prolonged symptoms after mTBI, which had previously been thought to be deleterious until research as such as been published in the recent decades.

It is proposed that exercise assessment and aerobic exercise training may reduce concussion-related physiological dysfunction by restoring autonomic balance and by improving autoregulation of cerebral blood flow. Controlled progressive aerobic exercise treatment may help to restore normal CBF regulation by conditioning the brain to gradually adapt to repetitive mild elevations of systolic blood pressure.3-5

Application:

• Obtain baseline (use of BALKE, BUFFALO CONCUSSION TREADMILL TEST, or Bike Test described in Kurowski 2016)
  • Treadmill or bike
    • Stationary bike program indicated if excess head movements are provoking on treadmill
  • Monitor vitals
    • HR, BP, RPE, & symptoms
  • Progress intensity until exacerbation
• Prescribe aerobic exercise program
  • Intensity: 80% of symptomatic duration OR symptomatic heart rate/RPE if patient able to self monitor
  • Frequency: 5 days a week, 4 to 6 weeks
  • Monitor symptom trends and modify program accordingly weekly
    • progress it!
• Consider multi-modal treatment
  • Though aerobic exercise seems beneficial in ameliorating prolonged symptoms, consider challenging your patient in other modes such as dual tasking, vestibular, balance, and sport specific exercises alongside your aerobic exercise treatment (see Gagnon 2016) for they may be symptomatic in some realms but not others.

Acknowledgements:

Anne Galgon, PT, PhD, NCS

Contact: Jackie Pedersen, Temple Class of 2017. jacqueline.pedersen@temple.edu

References:

1. Kurowski BG, Hugentobler J, Quatman-Yates C, Taylor J, Gubanich PJ, Altaye M, Wade SL. Aerobic Exercise for Adolescents With Prolonged Symptoms After Mild Traumatic Brain Injury: An Exploratory Randomized Clinical Trial.  J Head Trauma Rehabil. 2016 Apr 26. [Epub ahead of print] PubMed PMID: 27120294.

2.Gagnon I, Grilli L, Friedman D, Iverson GL. A pilot study of active rehabilitation for adolescents who are slow to recover from sport-related concussion. Scand J Med Sci Sports. 2016;26(3):299-306

3.Leddy JJ, Cox JL, Baker JG, Wack DS, Pendergast DR, Zivadinov R, Willer B. Exercise treatment for postconcussion syndrome: a pilot study of changes in functional magnetic resonance imaging activation, physiology, and symptoms. J Head Trauma Rehabil. 2013 Jul-Aug;28(4):241-9

4. 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 & Practice. 2012:1-7

5.Leddy JJ, Kozlowski K, Donnelly JP, Pendergast DR, Epstein LH, Willer B. A preliminary study of subsymptom threshold exercise training for refractory post-concussion syndrome. Clinical Journal of Sport Medicine. 2010;20(1):21-2