Acquired brain injuries

Acquired brain injury (ABI) refers to damage to the brain that occurs after birth. Causes include trauma from an external force (e.g. a direct blow to the head), hypoxia (lack of oxygen to the brain), substance abuse (e.g. alcohol), and tumours or infections (e.g. meningitis). Two other major causes of ABI are stroke and neurodegenerative conditions.

Consequences of ABI may include cognitive impairment (e.g. memory), physical impairment (e.g., high muscle tone and impaired coordination), behavioural impairment (e.g. impulsivity), as well as social isolation and poor mental health. However, the functional profile for a person with ABI can vary enormously; from someone who, for example, mobilises with a motorised wheelchair, is non-verbal and depends on personal support for self-care, to someone who is fully independent in employment, self-care and mobility.

How does exercise help with acquired brain injuries?

People with ABI are among the most physically inactive members of society and those with severe brain impairments are less active than those with mild to moderate impairments. This physical inactivity is harmful for health, fitness and function, and compounds the primary impairments resulting from ABI. There is strong scientific evidence that indicates:

  • Aerobic exercise improves cardiorespiratory fitness in people with ABI. The quantity and intensity of exercise required for improvements is similar to the general population.
  • Resistance training improves muscular strength in people with ABI. While the quantity and intensity of exercise required for improvements is similar to the general population, it should be noted that no studies have specifically investigated the effects of strength training on people with ABI who are affected by spastic hypertonia, an impairment that could potentially affect outcomes.
  • Regular functional exercise (e.g., sit-to-stand, walking, climbing stairs) can improve performance of every day life activities.
  • All forms of exercise can alleviate depressive symptoms as well as improve other aspects of mood and quality of life.

What type of exercise is best for acquired brain injuries?

Because the effects of ABI are very variable and the quantity and quality of research on this population is limited, specific, recommendations for exercise programs are not possible. However some general recommendations can be made.

People with ABI should aim to be as active as they physically can.  For optimal health, the recommended volumes of aerobic and strength exercise are the same as the general population:

  • Aerobic exercise: at least 30 minutes of moderate-intensity aerobic activity on five or more days per week, or at least 25 minutes of vigorous intensity on three or more days per week.
  • Strength exercise: for major muscle groups, three sets of 8-10 repetitions resistance exercises at moderate intensity.

These recommendations will initially be unachievable for many people with ABI, particularly for those with severe mobility impairments, multiple comorbidities and/or people who have been inactive for extended periods. It is therefore recommended that an Accredited Exercise Physiologist is involved in the program design and that they use their knowledge, skills and experience to ensure that initial training volumes and subsequent increases in training volume are individually tailored for the person affected by ABI.