NCT00693511

Brief Summary

The overall goal of this project is to examine the physiological and metabolic effects of a 16-week circuit-training (strength training + aerobic activities) program, with and without a behavioral component utilizing motivational interviewing, in 45 overweight Latina adolescent girls (14-18 years of age). This 16-week randomized control study will examine the incremental effects of the following 3 intervention groups on insulin sensitivity, insulin secretion, adiposity, and habitual and ad libitum physical activity:

  • Control group (delayed circuit training intervention; n=15)
  • Circuit training group (strength + aerobic training; 2 times per week; n=15)
  • Circuit training (same as above) + weekly motivational interviewing sessions (n=15) Specific Aim 1: To examine the effects of a 16-week circuit training program on adiposity, insulin dynamics, other associated hormones and adipocytokines, cardiorespiratory fitness, and muscular strength in overweight Latina adolescent girls. Hypothesis 1: Participation in the circuit-training program will result in significant improvements in both physiological and metabolic outcomes, including: a) body composition as measured by DEXA, b) fat distribution as measured by MRI, c) adipose tissue hormones (e.g. leptin, adiponectin, TNF-α) as measured by fasting blood samples, d) insulin sensitivity and secretion as measured by frequently sampled intravenous tolerance test, e) aerobic fitness as measured by the single stage submaximal treadmill test, and f) increase muscular strength as measured by repetition maximums. Specific Aim 2: To examine the incremental effects of adding the motivational interviewing sessions to the circuit training on self-selected ad libitum physical activity during a 5-hour observational period, habitual physical activity levels using 7 day accelerometry, and the meanings and motivation to exercise using questionnaires before and after the intervention. Hypothesis 2: The addition of motivational interviewing will encourage and empower participants to be more active outside of the intervention and foster healthy physical activity behaviors in daily life. Improvements in physical activity behaviors will lead to greater improvements in all other health outcomes listed in specific aim 1 compared to circuit training alone and control group.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
45

participants targeted

Target at P25-P50 for not_applicable

Timeline
Completed

Started Oct 2007

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

October 1, 2007

Completed
8 months until next milestone

First Submitted

Initial submission to the registry

June 5, 2008

Completed
4 days until next milestone

First Posted

Study publicly available on registry

June 9, 2008

Completed
2.2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 31, 2010

Completed
2 years until next milestone

Study Completion

Last participant's last visit for all outcomes

August 31, 2012

Completed
Last Updated

September 25, 2017

Status Verified

September 1, 2017

Enrollment Period

2.9 years

First QC Date

June 5, 2008

Last Update Submit

September 20, 2017

Conditions

Keywords

obesityadolescentsadiposityinsulin sensitivitytype 2 diabetesLatinocircuit trainingphysical activitymotivational interviewing

Outcome Measures

Primary Outcomes (1)

  • Insulin sensitivity

    post intervention (week 16)

Secondary Outcomes (3)

  • Change in waist circumference

    post-intervention (week 16)

  • Change in subcutaneous abdominal adipose tissue

    post-intervention (week 16)

  • Change in visceral abdominal adipose tissue

    post-intervention (week 16)

Study Arms (3)

Circuit Training

EXPERIMENTAL

Participants received CT exercise training two times per week for approximately 60-90 min per session for 16 wk

Behavioral: Circuit Training

Circuit training + motivational interviewing

EXPERIMENTAL

Participants in the CT + MI group received the same CT classes but also received four individual MI and four group MI sessions throughout the 16-wk program by two trained research staff

Behavioral: Circuit training + motivational interviewing

Control

NO INTERVENTION

No intervention

Interventions

Circuit Training (aerobic + strength training 2 times per week for 16 weeks)

Also known as: CT
Circuit Training

Circuit training (aerobic + strength training 2 times per week for 16 weeks) + motivational interviewing (4 individual + 4 group sessions)

Also known as: CT + MI
Circuit training + motivational interviewing

Eligibility Criteria

Age14 Years - 18 Years
Sexfemale
Healthy VolunteersYes
Age GroupsChild (0-17), Adult (18-64)

You may qualify if:

  • At Risk of Overweight and Overweight (age- \& sex-specific body mass index ≥ 85th percentile based on CDC BMI growth charts \[US Department of Health and Human Services, 2000\]. There will not be an upper BMI limit. In our experience, we have had numerous children above the 99th percentile for BMI complete the outcome measures, and this group could benefit greatly from participation.
  • Gender \& Age: Females from grades 9th to 12th (approximately 14-18 years of age). We chose to study adolescents because pubertal youth will likely possess the requisite hormonal milieu needed to elicit physiologically and metabolic changes in response to resistance and aerobic training. In addition physical activity declines are more pronounced in minority females. By limiting the study to just females, we will retain a more homogenous group. This will eliminate sensitive gender issues related to exercise such as body image concerns, goal setting, and motivations for behavioral changes. To reduce effects of the menstrual cycle, all females will be tested during the follicular phase, while those with irregular/unpredictable menses will be studied at random times.
  • Latino origin all four grandparents must be of Hispanic heritage (reported on screening forms). This approach is consistent with all of our previous and ongoing work.

You may not qualify if:

  • Presently taking medication(s) or diagnosed with any syndrome or disease that could influence physical activity, body composition and fat distribution, or insulin action.
  • Previously diagnosed with any major illness since birth (e.g. chronic birth asphyxia, cancer, etc.).
  • Children with type 1 and/or type 2 diabetes will be excluded and referred to a physician. Children with impaired glucose tolerance (fasting glucose \>100 mg/dL during a fasting blood draw) and/or conditions associated with insulin resistance (e.g. acanthosis nigricans, hypertension, dyslipidemia) will be eligible, as long as they are not receiving treatment and meet other eligibility criteria.
  • Children who have any physical, cognitive, or psychological disabilities that would prevent them from participating in an exercise program.
  • Currently, or in the past 6 months, involved with any dietary, physical activity or weight loss program.
  • Children who live farther than 20 miles away from the GCRC.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Veronica Atkins Lifestyle Intervention Laboratory

Los Angeles, California, 90033, United States

Location

Related Publications (2)

  • Davis JN, Gyllenhammer LE, Vanni AA, Meija M, Tung A, Schroeder ET, Spruijt-Metz D, Goran MI. Startup circuit training program reduces metabolic risk in Latino adolescents. Med Sci Sports Exerc. 2011 Nov;43(11):2195-203. doi: 10.1249/MSS.0b013e31821f5d4e.

  • Davis JN, Le KA, Walker RW, Vikman S, Spruijt-Metz D, Weigensberg MJ, Allayee H, Goran MI. Increased hepatic fat in overweight Hispanic youth influenced by interaction between genetic variation in PNPLA3 and high dietary carbohydrate and sugar consumption. Am J Clin Nutr. 2010 Dec;92(6):1522-7. doi: 10.3945/ajcn.2010.30185. Epub 2010 Oct 20.

MeSH Terms

Conditions

ObesityDiabetes Mellitus, Type 2Insulin ResistanceMotor Activity

Interventions

Circuit-Based ExerciseMotivational Interviewing

Condition Hierarchy (Ancestors)

OverweightOvernutritionNutrition DisordersNutritional and Metabolic DiseasesBody WeightSigns and SymptomsPathological Conditions, Signs and SymptomsDiabetes MellitusGlucose Metabolism DisordersMetabolic DiseasesEndocrine System DiseasesHyperinsulinismBehavior

Intervention Hierarchy (Ancestors)

Physical Conditioning, HumanExerciseMotor ActivityMovementMusculoskeletal Physiological PhenomenaMusculoskeletal and Neural Physiological PhenomenaDirective CounselingCounselingMental Health ServicesBehavioral Disciplines and ActivitiesHealth ServicesHealth Care Facilities Workforce and Services

Study Officials

  • Jaimie N Davis, PhD, RD

    University of Southern California

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
NIH
Responsible Party
SPONSOR

Study Record Dates

First Submitted

June 5, 2008

First Posted

June 9, 2008

Study Start

October 1, 2007

Primary Completion

August 31, 2010

Study Completion

August 31, 2012

Last Updated

September 25, 2017

Record last verified: 2017-09

Locations