Fat Metabolism in Response to Acute Diet- and Exercise-induced Changes in Energy Balance - Full Text View

Purpose

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.

Condition	Intervention
Cardiovascular Diseases	Behavioral: Positive energy balance Behavioral: Energy balance with exercise Behavioral: Negative energy balance Behavioral: Negative energy balance with exercise Behavioral: Energy balance

Study Type:	Interventional
Study Design:	Allocation: Randomized Intervention Model: Single Group Assignment Masking: Open Label Primary Purpose: Prevention
Official Title:	VLDL-triglyceride Metabolism in Response to Acute Diet- and Exercise-induced Changes in Energy Balance

Resource links provided by NLM:

MedlinePlus related topics: Diabetes Medicines Exercise and Physical Fitness

U.S. FDA Resources

Further study details as provided by Washington University School of Medicine:

Primary Outcome Measures:

Very Low Density Lipoprotein-Triglyceride and apoB-100 concentrations [ Time Frame: After acute (24 hour) changes in energy intake and/or energy expenditure ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

Liver Very Low Density Lipoprotein-Triglyceride and apoB-100 secretion rates [ Time Frame: After acute (24 hour) changes in energy intake and/or energy expenditure ] [ Designated as safety issue: No ]
Liver Very Low Density Lipoprotein-Triglyceride and apoB-100 clearance rates from plasma [ Time Frame: After acute (24 hour) changes in energy intake and/or energy expenditure ] [ Designated as safety issue: No ]
Plasma glucose concentration and turnover rate [ Time Frame: After acute (24 hour) changes in energy intake and/or energy expenditure ] [ Designated as safety issue: No ]
Plasma insulin concentration [ Time Frame: After acute (24 hour) changes in energy intake and/or energy expenditure ] [ Designated as safety issue: No ]
Plasma free fatty acid concentration and turnover rate [ Time Frame: After acute (24 hour) changes in energy intake and/or energy expenditure ] [ Designated as safety issue: No ]
Plasma glucose concentration [ Time Frame: During acute (24 hour) changes in energy intake and/or energy expenditure ] [ Designated as safety issue: No ]
Measured hourly over the 24 h period.
Plasma insulin concentration [ Time Frame: During acute (24 hour) changes in energy intake and/or energy expenditure ] [ Designated as safety issue: No ]
Measured hourly over the 24 h period.
Plasma free fatty acid concentration [ Time Frame: During acute (24 hour) changes in energy intake and/or energy expenditure ] [ Designated as safety issue: No ]
Measured hourly over the 24 h period.

Enrollment:	12
Study Start Date:	April 2006
Study Completion Date:	December 2012
Primary Completion Date:	December 2012 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Experimental: Positive energy balance Comparison between isocaloric and hypercaloric diets with no exercise performed in any trials	Behavioral: Positive energy balance Subjects will consume over a 24 hour period 33% more calories than they require to meet their energy demands. Behavioral: Energy balance Subjects will consume over a 24 hour period a sufficient amount of calories to meet their energy needs.
Experimental: Energy balance with exercise 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.	Behavioral: Energy balance with exercise Subjects will consume over a 24 hour period 33% more calories than they require to meet their energy demands but will perform 2 hours of exercise that will be sufficient to burn off the excess calories consumed resulting in subjects being in net energy balance. Behavioral: Energy balance Subjects will consume over a 24 hour period a sufficient amount of calories to meet their energy needs.
Experimental: Negative energy balance Comparison between isocaloric and hypocaloric diets with no exercise performed in any trials	Behavioral: Negative energy balance Subjects will consume over a 24 h period only 66% of the calories required to meet their energy demands such that they will be in a net negative calorie balance in this trial. Behavioral: Energy balance Subjects will consume over a 24 hour period a sufficient amount of calories to meet their energy needs.
Experimental: Negative energy balance with exercise 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.	Behavioral: Negative energy balance with exercise Subjects will consume over a 24 hour period the same amount of calories as ingested in the isocaloric trial but will also perform 2 hours of exercise that will be sufficient to burn off a third of the calories they consumed during this day resulting in subjects being in net negative energy balance in this trial Behavioral: Energy balance Subjects will consume over a 24 hour period a sufficient amount of calories to meet their energy needs.

Detailed 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.

Eligibility

Ages Eligible for Study:	21 Years to 50 Years
Genders Eligible for Study:	Male
Accepts Healthy Volunteers:	Yes

Criteria

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.

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00830999

Locations

United States, Missouri
Washington University in Saint Louis
Saint Louis, Missouri, United States, 63110

Sponsors and Collaborators

Washington University School of Medicine

Investigators

Principal Investigator:

Bettina Mittendorfer, PhD

Washington University School of Medicine

More Information

No publications provided

Responsible Party:	Washington University School of Medicine
ClinicalTrials.gov Identifier:	NCT00830999 History of Changes
Other Study ID Numbers:	05-0195
Study First Received:	January 26, 2009
Last Updated:	January 18, 2013
Health Authority:	United States: Institutional Review Board

Keywords provided by Washington University School of Medicine:

fat metabolism
exercise
liver
lipoproteins
triglycerides

Additional relevant MeSH terms:

Cardiovascular Diseases

ClinicalTrials.gov processed this record on May 23, 2013

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