Fat Metabolism in Response to Acute Diet- and Exercise-induced Changes in Energy Balance (DEV)

The Washington University

Status: Completed

Conditions: Cardiovascular Diseases

Treatments: Behavioral: Positive energy balance; Behavioral: Negative energy balance with exercise; Behavioral: Energy balance with exercise; Behavioral: Negative energy balance; Behavioral: Energy balance

Study type: Interventional

Funder types: Other

Identifiers

NCT00830999

05-0195

Details and patient eligibility

About

This study is being conducted to learn more about the role of diet and exercise in regulating plasma triglyceride (fat) metabolism. The investigators will examine the effect of acute (24 hour) changes in energy intake and expenditure on fat metabolism the following day.

Full description

Excess body fat and a sedentary lifestyle are associated with increased plasma triglyceride (TG) and apolipoprotein B-100 (apoB-100) concentrations, which are important risk factors for the development of cardiovascular disease.

Weight loss and endurance exercise improve plasma lipid and lipoprotein concentrations. However, the mechanisms responsible for this effect are largely unknown, and much uncertainty remains regarding the independent roles of dietary energy intake, exercise energy expenditure, and net energy balance in controlling plasma TG concentrations.

The main goal of this project, therefore, is to investigate the mechanisms by which acute alterations in energy balance, induced by diet and/or physical activity (endurance exercise), regulate very-low density lipoprotein (VLDL) metabolism.

Subjects will be asked to perform 3 separate trials. One of these will always be an "energy balance" trial that will act as the control trial for the other 2 trials they perform. Subjects will therefore be randomized to 2 different study arms.

Enrollment: 12 patients

Sex: Male

Ages: 21 to 50 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• overweight and obese men
• normal to mild hypertriglyceridemia

Exclusion criteria

• Smoking
• Any medical condition other than increased body weight (e.g. diabetes, heart disease, etc.).
• Use of drugs known to affect lipid metabolism (e.g. statins, etc.).
• Regular exercise training.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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12 participants in 4 patient groups

Positive energy balance

Experimental group

Description:

Comparison between isocaloric and hypercaloric diets with no exercise performed in any trials

Treatment:

Behavioral: Positive energy balance

Behavioral: Energy balance

Energy balance with exercise

Experimental group

Description:

Comparison between an isocaloric diet without exercise and a hypercaloric diet with a sufficient amount of exercise performed to match the excess calories consumed resulting in both trials being in net energy balance.

Treatment:

Behavioral: Energy balance with exercise

Behavioral: Energy balance

Negative energy balance

Experimental group

Description:

Comparison between isocaloric and hypocaloric diets with no exercise performed in any trials

Treatment:

Behavioral: Energy balance

Behavioral: Negative energy balance

Negative energy balance with exercise

Experimental group

Description:

Comparison between consuming an isocaloric diet without exercise and consuming the same amount of calories as in the isocaloric trial but with exercise performed resulting in net negative energy balance in the exercise trial.

Treatment:

Behavioral: Negative energy balance with exercise

Behavioral: Energy balance