Circuit Training and Motivational Interviewing to Reduce Type 2 Diabetes in Youth

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.

Conditions

• Obesity and Type 2 Diabetes

Interventions

BEHAVIORAL

Circuit Training

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

BEHAVIORAL

Circuit training + motivational interviewing

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

Sponsors & Collaborators

• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

  lead NIH

Principal Investigators

• Jaimie N Davis, PhD, RD · University of Southern California

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

14 Years

Max Age

18 Years

Sex

FEMALE

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2007-10-31

Primary Completion

2010-08-31

Completion

2012-08-31

Countries

• United States

Study Locations