Aerobic Training and Non-Exercise Physical Activity

Not Applicable

Completed

Conditions: Obesity
Central Obesity

Interventions: Behavioral: Aerobic Exercise+ Physical Activity
Behavioral: Aerobic Exercise Training

Registration Number: NCT02010060

Lead Sponsor: East Carolina University

Brief Summary: This study will determine the health benefits of combining exercise training and increasing the amount of physical activity in daily life on the fat around the abdomen, weight, fitness and sensitivity to insulin. Volunteers will participate in one of three groups for 6 months: 1) a control group, 2) exercise training only, or 3) exercise training and increasing physical activity outside of training. The exercise training will follow the public health recommendations for exercise (150 minutes/week of moderate exercise). The group increasing physical activity along with exercise training will be asked to increase physical activity in their daily life (up to 3,000 step/day above their current levels through the use of step counters), and meetings focused on behavior modification. The investigators hypothesize that combining aerobic training and additional physical activity after training will have the most profound reduction on waist circumference and body composition.

Detailed Description: The Intervention Composed of Aerobic Training and Non-Exercise Physical Activity (I-CAN) study will investigate the effects of aerobic exercise training and increasing the amount of physical activity outside of training (Non-EX PA) on waist circumference, weight, and other cardiovascular disease risk factors in a prospective pilot trial. The investigators will randomize sedentary (\<6,500 steps per day) obese adults with at least one additional cardiovascular risk factor (N= 45) to a: (1) structured aerobic exercise program with no intervention on Non-Ex PA (AERO group, N=15); (2) structured aerobic exercise program with the additional goal of increasing Non-EX PA (AERO-PA group, N=15), or (3) a non-exercise control group (CON, N=15) for 6 months. Exercise groups will participate in the same aerobic training program (50 to 75% VO2 max), designed to be consistent with public health recommendations of 150 minutes per week of moderate physical activity. Non-Ex PA in the AERO group will be tracked throughout the entire 6 month intervention with pedometers capable of counting steps, but not displaying them to the participant (blind mode capable). The AERO-PA group will progressively increase Non-Ex PA throughout intervention using pedometers (a progressive increase of 1,000 to 3,000 steps per day above baseline levels). The AERO-PA group will also participate in lifestyle counseling grounded in the principles of the behavioral change theories to determine/reinforce strategies to increase Non-Ex PA. The primary outcome measure will be change in waist circumference following the intervention. The results of this pilot study will be used to determine the efficacy/feasibility of the intervention, and power a larger trial as an R01 application.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 45

Inclusion Criteria

Age: 40 to 65 years
Body mass index: 30-40
Sedentary status
One additional risk factor for cardiovascular disease
High waist circumference

Exclusion Criteria

Previous heart attack or stroke
Type 1 or type 2 diabetes
Resting systolic blood pressure >180 mmHg
Resting diastolic blood pressure>100 mmHg
Plans to be away from the Pitt County area more than 4 weeks in the next 6 months
Currently pregnant or plans to become pregnant
Not full-filling requirements during the screening process
Currently using weight loss medications
Gastric banding surgery

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Aerobic Exercise+ Physical Activity	Aerobic Exercise+ Physical Activity	The goal of this group is to perform 6 months of aerobic exercise and increase the amount of physical activity outside of their training sessions. They will be asked to make no conscious changes to their dietary habits
Aerobic Exercise Training	Aerobic Exercise Training	The Aerobic training group will participate in 6 months of aerobic training and asked to make no conscious alterations in their physical activity outside of exercise session, or dietary habits

Primary Outcome Measures

Name	Time	Method
Change in Waist Circumference	Baseline and 24 weeks	Waist circumference will be measured at the natural waist (midway between the inferior border of the rib cage and the superior aspect of the iliac crest) with a Gulick tape measure. Both landmarks (the inferior border of the ribcage and the superior aspect of the iliac crest) will be marked and the distance will be measured to determine the appropriate measurement site. Staff will confirm that: 1) the measurement tape remains horizontal; 2) the tape touches the entire circumference of the participant; 3) abdominal tissue is not compressed; 3) the tape measure is not within abdominal folds; 4) the measurement is taken at the end of normal respiration. The measurement will be repeated an additional time, and the reported value will be the average of these measurements. Both measurements must be within 0.5 cm to be considered acceptable for data purposes.

Secondary Outcome Measures

Name	Time	Method
Change in High Density Lipoprotein (HDL)	Baseline and 24 Weeks	HDL cholesterol level will be measured from a blood sample at baseline and follow-up
Change in Total Cholesterol (mg/dL)	Baseline and 24 weeks	Total cholesterol will be measured by a blood sample at baseline and 24 weeks
Change in Triglyceride Level	Baseline and 24 Weeks	Change in triglycerides will be measured from a blood sample at baseline and 24 weeks
Change in Glucose	Baseline and 24 weeks	Glucose concentration from a fasting blood sample will be measured at baseline and follow-up
Change in C-reactive Protein	Baseline and 24 weeks	High sensitivity c-reactive protein (inflammatory marker) will be measured at baseline and follow-up
Changes in Steps	Baseline and 24 Weeks	Participants will wear an accelerometer for seven consecutive days, 24-hrs/day. The amount of steps will be calculated
Change in Body Fat	Baseline to 24 weeks	Dual-energy X-ray absorptiometry will be used to measure changes in fat and lean mass.
Change in Body Weight	Baseline and 24 weeks	Weight will be measured using a standardized scale
Change in Cardiorespiratory Fitness (L/Min)	Baseline and 24 weeks	Fitness will be measured using a modified Balke protocol on a treadmill. Participants will walk at an initial speed of 2.0 mph with 0% grade for the first 3 minutes after which the treadmill speed will increase to 3.0 mph for the next 3 minutes. The treadmill grade will be increased by 2.5% every 3 minutes until volitional exhaustion. Respiratory gases (VO2, CO2) and ventilation will be measured continuously using a True Max 2400 Metabolic Measurement Cart (Parvomedics, Salt Lake City Utah).
Change in Insulin Sensitivity	Baseline and 24 Weeks	Insulin sensitivity was measured using an oral glucose tolerance test. With the results of the oral glucose tolerance test at baseline, insulin sensitivity was calculated with the Matsuda index. Insulin sensitivity was calculated with Matsuda index: \[10,000 / √glucose minute 0 x insulin minute 0) (mean glucose (OGTT) x mean insulin OGTT)\]. A higher result is better.
Change in Low Density Lipoprotein (LDL)	Baseline and 24 weeks	LDL level will be measured from a blood sample at baseline and follow-up.
Change in Caloric Intake (Kilocalories)	Baseline and 24 weeks	Food Frequency Questionnaire (FFQ) contains approximately 105 items grouped by categories and is completed for both frequency of consumption as well as portion size selections by the individual. The questionnaire, upon completion, provides estimated daily intake values for selected nutrients (kilocalories, macronutrients, and micronutrients) and provides information on food group servings.
Change in Insulin	Baseline and 24 Weeks	Insulin level will be measured from a fasting blood sample at baseline and at 24 weeks