Improving Individual Glycemic Response With Exercise Intensity
Condition: PreDiabetes; Diabetes Mellitus, Type 2; Exercise; Physical Activity
MeSH terms: Diabetes Mellitus, Type 2
Study type: Interventional

Summary: 
      Large interindividual variability exists in the glycemic response to exercise program,
      resulting in a subset of individuals known as exercise non-responders (NRs). Increasing the
      intensity of an exercise intervention has been proposed as one method for rescuing NRs by
      producing beneficial changes. However, this theory has not been tested on NRs classified
      using glycemic outcomes. This study will evaluate if increasing the intensity of an exercise
      intervention will elicit a response within previous exercise NRs.
    

Detailed description: 
      Exercise can effectively slow the progression towards Type 2 diabetes (T2D). However, data
      suggest large interindividual variability exists in glycemic response to exercise, resulting
      in a subset of individuals known as exercise non-responders (NRs). Emerging research proposes
      that altering the parameters of an exercise intervention to provide a sufficient stimulus can
      elicit a response in those previously identified as NRs. To date, no research has attempted
      to rescue previously classified NRs based on glycemic outcomes by altering the parameters of
      an exercise intervention.

      This study will implement an exercise program targeted at achieving the Canadian Physical
      Activity Guidelines, and calculate the number of NRs. We will then evaluate if increasing the
      intensity of exercise will elicit response to the treatment in the NRs.

      Sixty adults living with prediabetes or T2D will be recruited into one of a control group, or
      an exercise group. The exercising participants will begin a 16-week exercise intervention,
      targeted at achieving 150 minutes of moderate to vigorous intensity (equating to 4.5 METs)
      aerobic physical activity per week. Following the 16-week exercise program, participants will
      be randomized into two groups, each completing an additional 12 weeks of exercise. The first
      will maintain the same time and intensity, while the other will complete the 150 minutes per
      week at an intensity equal to 6.0 METs. Randomization will occur in blocks in order to ensure
      an equal number of NRs in each group.
    

Intervention name(s): Maintained Exercise; Increased Intensity
Intervention type(s): Behavioral; Behavioral
Intervention description(s): Complete 28 weeks of aerobic exercise, with one week (following week 16) for testing.
Week 1 - 16 Intensity: 4.5 metabolic equivalents (METs).
Duration:
Week 1: 80 minutes Week 2: 100 minutes Week 3: 120 minutes Week 4: 135 minutes Week 5 - 16: 150 minutes/week
Week 17: Physiological Testing
Week 18 - 29 Intensity: 4.5 METs Duration: 150 minutes/week
All exercise must be completed across a minimum of two sessions per week. Sub-maximal exercise tests will be completed every 4 weeks to adjust intensity.; Complete 28 weeks of aerobic exercise, with one week (following week 16) for testing.
Week 1 - 16 Intensity: 4.5 metabolic equivalents (METs).
Duration:
Week 1: 80 minutes Week 2: 100 minutes Week 3: 120 minutes Week 4: 135 minutes Week 5 - 16: 150 minutes/week
Week 17: Physiological Testing
Week 18 - 29 Intensity: 6.0 METs Duration: 150 minutes/week
All exercise must be completed across a minimum of two sessions per week. Sub-maximal exercise tests will be completed every 4 weeks to adjust intensity.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Participants will first be randomized as controls or exercisers. All exercisers will complete a 16 week exercise program, then be randomized into two groups. The first group will increase the exercise intensity and conduct another 12 week program. The second group will continue the original program for an additional 12 weeks.
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Exercise Response; Interindividual Variability