Exercise Program Combined or Not With Nutritional intErvention in Adults With tyPe 2 Diabetes
Condition: Overweight; Obesity; Type 2 Diabetes
MeSH terms: Diabetes Mellitus; Diabetes Mellitus, Type 2; Overweight
Study type: Interventional

Summary: 
      Inactivity and excess energy consumption are leading causes of obesity and type 2 diabetes
      which are associated with increased cardio-metabolic risk. In order to reduce the
      cardiovascular risk associated with type 2 diabetes, the Canadian Diabetes Association
      guidelines (2008) recommends weight loss through caloric restriction and structured physical
      activity. However, the comparative effects of different methods to obtain caloric deficit for
      weight loss remains to be elucidated. The main objective of this study is to assess the
      impact of two strategies of caloric deficit: diet alone or diet and exercise on total fat
      mass, epicardial fat and cardiovascular risk factors in overweight and obese adults with type
      2 diabetes and at high risk of cardiovascular disease.
    

Detailed description: 
      Type 2 diabetes is mainly caused by excess body weight due to lack of physical activity and
      high amount of calories consumption. Individuals with type 2 diabetes demonstrated increased
      risk of cardiovascular disease compared to non diabetic. Studies showed a cardiovascular risk
      reduction after weight loss among individuals at risk through lifestyle modification:
      increase physical activity and low calorie diet.

      Favourable effects of weight loss on cardiovascular risk are mainly due to total body fat
      reduction. However, the location of body fat excess has also some important implications. It
      is now well known that abdominal (visceral) and ectopic fat accumulation (e.g. hepatic fat,
      epicardial fat, etc.) are more related to an unfavorable cardio-metabolic profile than total
      fat mass. It has been demonstrated that a moderate weight loss obtained with physical
      activity or caloric restriction is related to a significant reduction of ectopic fat mass.
      However, ectopic fat measurement remains problematic due to lack of standardization and
      safety issues (X-ray). Epicardial fat thickness measured by simple echocardiography is a
      reliable method to evaluate ectopic fat accumulation.

      Little research have been done to assess the effect of different methods of weight loss on
      total fat as well as ectopic fat specifically epicardial adipose tissue among individuals
      with type 2 diabetes. The objective of this study is to compare to a control group with
      detailed advice the impact of two structured strategies of caloric deficit: diet alone or
      diet and exercise on total fat mass, epicardial fat and cardiovascular risk factors in
      overweight and obese adults with type 2 diabetes and at high risk of cardiovascular disease.

      The participants to the present study will be free-living adults overweight and obese with
      type 2 diabetes and at high risk of cardiovascular disease as determined by a Framingham risk
      score above 15% or the presence of two or more cardiovascular risk factors.

      Participants will attend a screening study visit to confirm eligibility criteria
      (anthropometric variables, blood pressure, complete physical examination, coronary heart
      disease diagnostic by echocardiogram, physical activity aptitude).

      After enrollment, a baseline visit will consist in series of data collection such as :
      anthropometric variables, blood pressure, cycle ergometer test to evaluate cardiovascular
      fitness, an echocardiography to determine epicardial fat thickness, a dual energy x-ray
      absorptiometry (DEXA) scan to assess body fat, lean mass and bone density, indirect
      calorimetry for resting metabolic rate, physical activity profile and total energy
      expenditure determined by Sense Wear Armband (SWA) accelerometer (7days), food consumption
      estimate with 3 days dairy, questionnaires addressing sociodemographic and psychosocial
      characteristics, diabetes self-care (SDCA questionnaire), a blood and urine collection for
      diabetes control, hepatic steatosis biochemical score, detailed lipids, hormonal and
      inflammatory profile and finally microalbuminuria. The body composition will also be measured
      by impedancemetry and BOD-POD.

      Participants will then be randomly assigned to one of the three groups of the study :

      Group 1: Counseling for physical activity and healthy eating Group 2: Structured diet
      intervention (caloric restriction) and counseling for physical activity Group 3: Structured
      diet intervention (caloric restriction) and structured exercise training program (aerobic and
      resistance training).

      Group 1: participants will attend one visit with the dietician (30mn) and the physical
      activity specialist (30mn) when they will be given Canadian guidelines pamphlets for physical
      activity and food consumption. They will also receive a phone call once a month to discuss
      about issues in guidelines following.

      Group 2: participants will attend one visit with the physical activity specialist (30mn) when
      they will receive the physical activity guidelines. Monthly phone call will be make to
      discuss about issues in physical activity guidelines following. These individuals will also
      be enrolled in a supervised caloric restriction program. They will have to visit the
      dietician once a week for the first months and then twice a month for 3 months. The diet
      intervention will focus on a low fat diet. At each session participants will be weighed and
      taken the blood pressure.

      Group 3: participants will attend diet intervention as described for group 2. They will also
      follow a supervised exercise program three days per week for 4 months. The exercise training
      is an interval high intensity aerobic (85-90% Heart rate reserve) program with resistance
      exercises (15RM, 2-3 repetitions). Each session will last one hour. At the end of month 1, 2,
      and 3, all participants will receive the SWA armband for 7 days to record physical activity
      and estimate energy expenditure.

      At the end of Month 4, all participants will attend a study visit for repeat baseline
      testing.
    

Intervention name(s): Caloric restriction; Diet intervention and structured exercise training program
Intervention type(s): Behavioral; Behavioral
Intervention description(s): The caloric restriction diet will follow the Canadian Diabetes Association guidelines and be nutritionally balanced with a reduced total fat as well as saturated content.; Participants will follow the diet intervention previously described and a supervised physical activity program. The supervised exercise training sessions will take place three times a week for 4 months. Each session will last 1hour and will include aerobic exercise and resistance training. The aerobic training program will be treadmills intervals exercise at 50-70 % of heart rate reserve(HRR) the first month and 85-90% of HRR from the second to the fourth month. The resistance training programme will consist of two to three sets of 12 repetitions of the following exercises: leg press, chest press, lat pulldown, shoulder press, biceps curl, triceps extension.
Other intervention name(s): Structured diet intervention (caloric restriction); diet intervention and exercise program.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: overweight; obesity; type 2 diabetes; caloric restriction; exercise program; epicardial fat