Clinical trial NCT03576924: Power of Choice on Autonomy, Motivation, Exercise Adherence, and Cardiorespiratory Fitness
Official title: The Power of Choice on Autonomy Support, Motivation, Exercise Adherence and Cardiorespiratory Fitness Among Adults With Elevated Blood Glucose
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Elevated Blood Sugar
Keywords: Autonomy Support
Exercise Motivation
Physical Activity Adherence
Cardiorespiratory Fitness
Prediabetes
Lead sponsor: University of British Columbia
Sponsor class: OTHER
Collaborators: name: Heart and Stroke Foundation of Canada
First posted: 2018-07-05
Enrollment: 77
Sex: ALL
Minimum age (years): 18
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: This is a single-centre, 3-arm parallel-group randomized trial.
Primary purpose: PREVENTION

Brief summary: People with elevated blood sugar levels are at increased risk of developing chronic medical conditions such as obesity, type 2 diabetes, and cardiovascular disease. Improving cardiorespiratory fitness (CRF) in adults with elevated blood sugar levels is important for preventing the onset of such medical conditions. The primary aim of this study is to determine whether providing a choice between two different types of exercise in a diabetes prevention intervention improves perceived autonomy, exercise motivation, physical activity behavior, and subsequently CRF to a greater extent than imposed exercise among adults with elevated blood sugar.

Detailed description: This trial has been informed by self-determination theory. The theory states that individuals who choose their own activities report increased autonomy and internal reasons/motivations to change a behavior as opposed to external reasons (to satisfy another person's suggestions). Perceived autonomy support and internal motivation for performing a behavior are linked with improved long-term adherence to the behavior change, which subsequently leads to physiological adaptations such as an increase in CRF.

The primary outcome of this study is participants' perceived autonomy support after a 4-week diabetes prevention program. The secondary outcomes are 1) changes in exercise-related motivation from baseline to immediately post-intervention and 6-months post-intervention, 2) physical activity behavior 6-months post-intervention while controlling for baseline values, and 3) CRF 6-months post-intervention while controlling for baseline values. Seventy-seven low-active adults between 18-75 years of age with elevated blood sugar levels (HbA1c between 5.7%-6.4% or American Diabetes Association risk assessment \>5) have been randomized to a 4-week supervised intervention involving behavioral counseling and one of three exercise conditions: 1) imposed high-intensity interval training (HIIT; n=26); 2) imposed moderate-intensity continuous training (MICT; n=26), or 3) choice between MICT or HIIT (CHOICE; n=24). It is hypothesized that when compared to HIIT and MICT, the CHOICE condition will have greater perceived autonomy support immediately after the 4-week intervention, display more internal motivation immediately after the 4-week intervention, and show greater improvements in physical activity adherence and CRF 6-months post-intervention. This proposed trial will provide theory- and evidence-based information whether providing choice for engaging in HIIT or MICT is associated with greater improvements in perceived autonomy support, motivation regulation, physical activity behavior, and CRF.

Eligibility criteria: Inclusion Criteria:

* BMI 22-45 kg/m2;
* HbA1c score indicative of elevated blood sugar (5.7-6.4%);
* Blood pressure of \<160/99 mm Hg assessed according to Canadian Hypertension Education Program guidelines;
* Without diagnosed diabetes;
* No prior history of cardiovascular disease;
* Not on hormone replacement therapy;
* Not on beta-blockers;
* Cardiovascular medications (e.g., statins) will be allowed if patients are on stable therapy (6 months on same dose)

Exclusion Criteria:

* Taking glucose-lowering medications (i.e. metformin);
* Any explicit contraindications to exercise (e.g., musculoskeletal injury)

Primary outcomes:
measure: Perceived Autonomy Support
timeFrame: Four weeks post-intervention.
Secondary outcomes:
measure: Change in Exercise Motivation Regulation
timeFrame: Baseline, four weeks post-intervention, and 6 months post-intervention
measure: Change in Physical Activity Behavior (Self-Report)
timeFrame: Baseline, 6-months after the intervention
measure: Change in Physical Activity Behavior (Accelerometry)
timeFrame: Baseline, 6 months after the intervention
measure: Change in Physical Activity Behavior (Fitbit)
timeFrame: Baseline, 6 months after intervention
measure: Change in Cardiorespiratory Fitness
timeFrame: Baseline, 6 months after intervention
Other outcomes:
Locations:
city: Kelowna
country: Canada
facility: University of British Columbia
state: British Columbia
Study officials:
affiliation: University of British Columbia
name: Mary E. Jung, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Little JP, Safdar A, Wilkin GP, Tarnopolsky MA, Gibala MJ. A practical model of low-volume high-intensity interval training induces mitochondrial biogenesis in human skeletal muscle: potential mechanisms. J Physiol. 2010 Mar 15;588(Pt 6):1011-22. doi: 10.1113/jphysiol.2009.181743. Epub 2010 Jan 25.
citation: Little JP, Gillen JB, Percival ME, Safdar A, Tarnopolsky MA, Punthakee Z, Jung ME, Gibala MJ. Low-volume high-intensity interval training reduces hyperglycemia and increases muscle mitochondrial capacity in patients with type 2 diabetes. J Appl Physiol (1985). 2011 Dec;111(6):1554-60. doi: 10.1152/japplphysiol.00921.2011. Epub 2011 Aug 25.
citation: Hood MS, Little JP, Tarnopolsky MA, Myslik F, Gibala MJ. Low-volume interval training improves muscle oxidative capacity in sedentary adults. Med Sci Sports Exerc. 2011 Oct;43(10):1849-56. doi: 10.1249/MSS.0b013e3182199834.
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citation: O'Donovan G, Owen A, Bird SR, Kearney EM, Nevill AM, Jones DW, Woolf-May K. Changes in cardiorespiratory fitness and coronary heart disease risk factors following 24 wk of moderate- or high-intensity exercise of equal energy cost. J Appl Physiol (1985). 2005 May;98(5):1619-25. doi: 10.1152/japplphysiol.01310.2004. Epub 2005 Jan 7.
citation: Jung ME, Bourne JE, Little JP. Where does HIT fit? An examination of the affective response to high-intensity intervals in comparison to continuous moderate- and continuous vigorous-intensity exercise in the exercise intensity-affect continuum. PLoS One. 2014 Dec 8;9(12):e114541. doi: 10.1371/journal.pone.0114541. eCollection 2014.
citation: Jung ME, Bourne JE, Beauchamp MR, Robinson E, Little JP. High-intensity interval training as an efficacious alternative to moderate-intensity continuous training for adults with prediabetes. J Diabetes Res. 2015;2015:191595. doi: 10.1155/2015/191595. Epub 2015 Mar 30.
citation: National Research Council (US) Panel on Handling Missing Data in Clinical Trials. The Prevention and Treatment of Missing Data in Clinical Trials. Washington (DC): National Academies Press (US); 2010. Available from http://www.ncbi.nlm.nih.gov/books/NBK209904/
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