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Effects of Images Following Long-term Aerobic Exercise on Brain Activation (E-Mech Anc II)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02162524
Recruitment Status : Withdrawn
First Posted : June 12, 2014
Last Update Posted : January 11, 2016
Information provided by (Responsible Party):
John Apolzan, Pennington Biomedical Research Center

Tracking Information
First Submitted Date  ICMJE September 17, 2013
First Posted Date  ICMJE June 12, 2014
Last Update Posted Date January 11, 2016
Study Start Date  ICMJE January 2014
Estimated Primary Completion Date July 2015   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: June 10, 2014)
fMRI [ Time Frame: baseline and post (6 month intervention) ]
fMRI will be performed using a General Electric Signa Excite HDxT 3.0T scanner (Milwaukee, WI) approximately 10 minutes post beverage ingestion. The field of view is 24-28 cm. The scanner is equipped with functional components from GE. Supplemental components include a projection system and eye imaging system from Avotec , Inc. An eight channel head coil will be utilized for all fMRI scans, and E-prime® software will be utilized for computerized experiment design, data collection, and analysis. Visual food and control cues will be presented in a mixed event block design with blocks of HS/HF and control images. Food cues consist of full-color pictures displaying foods within a category (HS/HF). One food item will be shown in each picture. Control cues consist of scrambled images that match the food cues in color intensity and frequency. Each block is 30s in length and 6 images are presented anywhere from 3-7seconds. Total task time will be ~30 minutes.
Original Primary Outcome Measures  ICMJE Same as current
Change History
Current Secondary Outcome Measures  ICMJE Not Provided
Original Secondary Outcome Measures  ICMJE Not Provided
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE Effects of Images Following Long-term Aerobic Exercise on Brain Activation
Official Title  ICMJE Effects of Images Following Long-term Aerobic Exercise on Brain Activation (E-Mechanic Ancillary II)
Brief Summary

The primary purpose of this study is to quantify activation of regions of the brain associated with appetite and reward after viewing high sugar and high fat (HS/HF) images compared to control images following long-term aerobic exercise.

  1. After long-term aerobic exercise compared to a no-exercise control group, viewing HS/HF food images vs. control images will result in higher activation of regions of the brain associate with appetite (hypothalamus).
  2. After long-term aerobic exercise compared to a no-exercise control group consumption of a sucrose solution compared to an artificially sweetened solution and a tasteless solution, viewing HS/HF food images vs. control images will result in lower activation of regions of the brain associated with reward [amygdala, anterior cingulate cortex (ACC), Orbitalfrontal Cortex (OFC), and ventral tegmental area (VTA), striatum, insula] in overweight and obese men and women.

Exploratory Aims As exploratory aims, investigators will test a preliminary brain connectivity analysis.

Detailed Description

In this pilot study, investigators will use functional magnetic resonance imaging (fMRI) to determine the effects of high calorie visual food cues [i.e. images of foods that are high in both sugar and fat (HS/HF), such as ice cream] on activation of appetite and reward pathways in the brain following long-term (6 months) exercise. Obesity rates are high among US adults with 33.8% of adults having a BMI of 30 or greater (1). The prevailing belief is that homeostatic systems are in place to monitor energy homeostasis.

With aerobic physical activity, appetite is affected because a theoretically positive coupling between energy intake and expenditure is thought to occur (2, 3). During exercise days, short term studies have demonstrated that there are no differences in appetite except for a transient decrease 15 minutes post exercise after very hard exercise(4). Short term exercise does not result in appetitive differences (5-7). However in the medium term, there is a variable (mixed) response (5). Over the long-term it is thought a loose coupling exists between exercise and appetite response (5).

Our preliminary data strongly support a positive coupling between exercise and appetitive responses because in previous studies the amount of weight loss that is achieved following aerobic exercise is less than expected. Specifically, studies by Tim Church have previously found that hypertensive overweight postmenopausal women did not lose ~2.6 kg but instead 1.4 kg (8). This is a 46% difference between how much weight should be lost due to energy expended with exercise compared to the actual amount. Another study examined 4 months of moderate intensity aerobic exercise of 16KKW (9) and again about 2.7 kg of weight loss was expected but only 1.1 kg was achieved. This suggests a 59% difference. Both studies had very low dropout rates. Based on the results of the highest dose of exercise in these two studies, the discrepancy grows with an increase in exercise dose. The participants were instructed not to change eating habits and physical activity outside of the intervention and these were not significantly altered. These body weight responses mirror the majority of aerobic exercise intervention studies. King et al. performed a supervised aerobic exercise study (10). 58 persons completed 500 kcal/d of exercise induced energy expenditure for 5 d/wk over 12 weeks with a 28% dropout rate. Overall an average of just 3.2 kg of body weight was lost. Over 50% of persons failed to lose the expected amount and 15% of persons gained weight (11). Four out of ten studies in a review found exercise did not even result in a body weight difference between the exercise and control groups(12). This differential response in energy balance is thought to be driven by increased energy intake. Stubbs et al. performed a randomized crossover study with 3-7 day exercise treatments. The exercise treatments were no exercise, then medium exercise (~1.9 MJ/day) and lastly high exercise (~ 3.4MJ/day). Energy expenditure increased in the no exercise (9.2 MJ/day), medium exercise (11.0 MJ/day) and high exercise conditions (12.1 MJ/day), respectively. A statistically significant increase in energy intake with exercise was found (no exercise 8.9 MJ/day, medium exercise 9.2 MJ/day, and high exercise 10.0 MJ/d). Thus based on body weight and these energy intake data from Stubbs et al. investigators feel there is a biological drive to increase energy intake following exercise. Investigators seek to determine the neural mechanism of this appetitive response in the proposed grant.

Previously 2 aerobic exercise studies examining for the neuronal response to images have been performed. Ours are similar and will provide PBRC with pilot data for further investigations. Evero et al. previously found that reward pathway neuronal cues were reduced following aerobic exercise (13). Cornier et al. found that chronic exercise alters the neuronal response to food cues. However this study was confounded due to significant weight loss which as stated above does not generally happen with aerobic exercise trials. The results suggested the insula may be particularly important in exercise induced weight loss and weight loss maintenance (14). This study hopes to examine the neuronal responses to aerobic exercise without weight loss.

Obesity Women were shown food picture cues of high energy foods. The high energy foods produced significantly greater activation in the brain reward regions in obese compared to normal weight control women (15). Differences between groups included ACC, VTA, nucleus accumbens (NAc), amygdala, ventral pallidum (Vent Pall), Caudate, and Putamen (15). Postmeal, obese individuals, but not normal weight individuals, increase activation of the putamen (part of striatum) and amygdala suggesting these regions may play a role in overeating (16) which is why these regions are incorporated into the current study hypothesis. These cross-sectional studies are important as previously Murdaugh et. al (17) found that obese individuals that were not successful at short term weight loss or longer term weight loss maintenance had greater activation of reward pathway brain regions. While speculative, artificial sweeteners may reduce cravings by not activating reward pathways especially in obese persons. This grant will help provide pilot data to further elucidate this important question.

Study Type  ICMJE Interventional
Study Phase  ICMJE Not Applicable
Study Design  ICMJE Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Primary Purpose: Treatment
Condition  ICMJE Obesity
Intervention  ICMJE Behavioral: Aerobic Exercise
The exercise groups will be closely monitored during exercise sessions for six months in our exercise-training laboratory. The intensity will be 65% VO2peak and all exercise will occur on a treadmill. One exercise group will obtain 8 KKW (kcal/kg/week) over 3-4 sessions per week, which will result in each session lasting approximately 30 minutes. The other exercise group will obtain 20 KKW, performing 4-5 sessions per week for approximately 50-70 minutes per session. These groups are combined for this ancillary study.
Other Names:
  • 8KKW
  • 20KKW
Study Arms  ICMJE
  • No Intervention: No Exercise Control
    Healthy Living Group
  • Active Comparator: Aerobic Exercise Group
    Persons are aerobically exercising.
    Intervention: Behavioral: Aerobic Exercise
Publications * Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Withdrawn
Actual Enrollment  ICMJE
 (submitted: June 10, 2014)
Original Actual Enrollment  ICMJE Same as current
Estimated Study Completion Date  ICMJE July 2015
Estimated Primary Completion Date July 2015   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria:

  • Male or Female
  • 18-65 years old (inclusive)
  • Weigh less than 350 lbs
  • Body mass index (BMI) between 25-43 kg/m2
  • Willing to fast for 10 hours prior to examination
  • Right handed

Exclusion Criteria:

  • Diagnosis (by self report) of diabetes
  • Diagnosis (by self report) of neurological condition
  • Current or past alcohol or drug abuse problem
  • Smoking
  • Have internal metal medical devices including cardiac pacemakers, aortic or cerebral aneurysm clips, artificial heart valves, ferromagnetic implants, shrapnel, wire sutures, joint replacements, bone or joint pins/rods/screws/clips, metal plates, metal fragments in your eye, or non-removable metal jewelry such as rings
  • Unable or unwilling to complete the imaging procedures for the duration of the MRI scan due to claustrophobia or other reason
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 18 Years to 65 Years   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE Yes
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE United States
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT02162524
Other Study ID Numbers  ICMJE PBRC 2013-045
Has Data Monitoring Committee No
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement  ICMJE Not Provided
Responsible Party John Apolzan, Pennington Biomedical Research Center
Study Sponsor  ICMJE Pennington Biomedical Research Center
Collaborators  ICMJE Not Provided
Investigators  ICMJE
Principal Investigator: John W Apolzan, PhD PBRC
PRS Account Pennington Biomedical Research Center
Verification Date January 2016

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP