Brain Exercise and Addiction Trial
Condition: Cannabis Use Disorder, Moderate; Cannabis Use Disorder, Severe
MeSH terms: Marijuana Abuse
Study type: Interventional

Summary: 
      Heavy cannabis use is associated with substantive learning and memory impairments and
      elevated risk of psychopathology. It has been repeatedly demonstrated that the hippocampus,
      centrally implicated in these processes, is particularly vulnerable to the deleterious
      effects of prolonged exposure to cannabis. This deterioration of hippocampal structure,
      function, and biochemistry can be reversed, but this requires two or more years of abstinence
      from cannabis. However, most heavy cannabis users find it extremely difficult to maintain
      abstinence over extended periods and current treatments for cannabis use disorders are
      inadequate. There is a pressing clinical need for an intervention that rapidly accelerates
      hippocampal recovery, ameliorates the associated cognitive impairments and mental health
      symptoms, and leads to improved treatment outcomes. One promising candidate is physical
      exercise. In addition to the well-known physical health benefits, regular exercise also has a
      potent positive effect on brain health. The current study will investitive the capacity of
      two different neuroscientifically-informed 12-week exercise programs can restore brain health
      for heavy long term cannabis users.
    

Detailed description: 
      Heavy cannabis use is associated with substantive learning and memory impairments and
      elevated risk of psychopathology. It has been repeatedly demonstrated that the hippocampus,
      centrally implicated in these processes, is particularly vulnerable to the deleterious
      effects of prolonged exposure to cannabis. This deterioration of hippocampal structure,
      function, and biochemistry can be reversed, but this requires two or more years of abstinence
      from cannabis. However, most heavy cannabis users find it extremely difficult to maintain
      abstinence over extended periods and current treatments for cannabis use disorders are
      inadequate. There is a pressing clinical need for an intervention that rapidly accelerates
      hippocampal recovery, ameliorates the associated cognitive impairments and mental health
      symptoms, and leads to improved treatment outcomes. One promising candidate is physical
      exercise. In addition to the well-known physical health benefits, regular exercise also has a
      potent positive effect on brain health and can increase the size of the hippocampus. It's not
      yet known how much or what kind of exercise produces the best results. This study has been
      designed to compare the effects of two different exercise programs.

        1. 12 weeks of regular HIIT exercise

        2. 12 weeks of regular strength training

      The research team are investigating whether the programs have a positive impact on brain
      health and, if they do, whether one is more effective than the other. The research team will
      also measure whether engaging in either program leads to a reduction in cannabis consumption,
      and improvements in thinking skills, mental health, and general wellbeing.
    

Intervention name(s): High Intensity Interval Training; Strength and Resistance Training
Intervention type(s): Behavioral; Behavioral
Intervention description(s): Exercise sessions will commence with an initial 3-week accustomization period whereby training load will increase incrementally from 2 x 45min sessions with effort peaking at 60% VO2 max (week 1) increasing to 3 x 45minute with effort peaking at 80% VO2max (week 3). Participants will transition to the full HIIT protocol for the remaining weeks. The HIIT component will comprise a work-rest ratio of ≥1:1minutes, with alternating exertion epochs at >80% VO2max and <60% VO2max. As VO2max is likely to increase as fitness improves toward the end of the 3-month program, adjustments to HIIT will be made by the exercise physiologist based on real-time heart rate monitoring, ensuring greater accuracy in participants achieving their heart rate targets.; Exercise sessions will comprise a combination of strength, coordination and mobility exercises. The strength component will consist of 2-3 sets of resistance exercises at ≤70% of a predicted 1 repetition maximum, targeting all body segments. Heart rate tracking will occur to ensure participants do not exceed 70% v02 (or exceed Lactate Threshold).
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment