Exercise Dose-Response on Features of the Metabolic Syndrome

Obesity Clinical Trial

Official title:

Dose-Response Effects of Aerobic Exercise on Insulin Sensitivity and the Metabolic Syndrome

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00687128
• Other study ID #: 04-10-788
• Secondary ID: U54RR014616
• Status: Completed
• Phase: N/A
• First received: May 27, 2008
• Last updated: February 24, 2012
• Start date: October 2004
• Est. completion date: April 2010

Study information

• Verified date: February 2012
• Source: Charles Drew University of Medicine and Science
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

This study investigates the degree of improvement in insulin resistance and features of the metabolic syndrome in non-diabetic overweight or obese subjects after training in a low-intensity, moderate-intensity or non-aerobic exercise program, as well as self-initiated exercise behavior after the assigned exercise program.

Description:

The proposed study is a randomized, open study comparing low-intensity and moderate-intensity aerobic exercise versus non-aerobic (stretching) exercise on direct measurements of insulin resistance and variables associated with the metabolic syndrome. This 6-month intervention will be followed by an additional 6-month follow-up period during which subjects will be encouraged to maintain their exercise regimen (along with their prescribed diet) but without scheduled supervision. Behavioral variables associated with adherence will be analyzed along with changes in the above physiological variables.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 93
• Est. completion date: April 2010
• Est. primary completion date: September 2009
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 60 Years

Eligibility

Inclusion Criteria:

• Males or females, age 18-60

• At least 2 of the 5 components of the NCEP definition of the metabolic syndrome, provided that either the triglyceride or waist circumference criteria are met

• Body mass index of 25-45 kg/m2

• Subjects not currently following a regular exercise program nor an optimal diet, and who self-report their activity level as sedentary

• Able to understand and sign the informed consent form, follow the instructions given in the study, attend all necessary clinic visits, and undergo all required study procedures

Exclusion Criteria:

• Past or current diabetes mellitus

• Significant concurrent medical illnesses (chronic liver or renal disease, malignancies, recent or chronic infections including HIV, surgeries or other hospitalizations within four weeks prior to screening), uncontrolled hypertension (BP >160/90 mm Hg), or abnormal TSH on screening.

• Conditions that may contraindicate physical activity (clinically significant cardiac, pulmonary, orthopedic, rheumatological or neurological diseases)

• Cardiovascular disease not controlled with medical therapy, or invasive vascular procedures within six months prior to screening

• Subjects found on resting EKG or stress testing to have underlying cardiac abnormalities

• Perimenopausal women who are experiencing irregular menses

• Pregnant or lactating women

• Subjects who may have limited exercise tolerance because of treatment with ß-adrenergic blockade agents, at least until agents of alternate drug classes can be substituted

• Subjects with concurrent endocrinopathies

• Subjects receiving concurrent treatment with metformin, thiazolidinediones, systemic glucocorticoids, or any weight loss agents

• Subjects who expect to require medications during the course of the study that may affect their metabolic profile, including systemic glucocorticoids and hormone replacement therapies

• Subjects who cannot complete the stress test due to physical limitations

• Any other factors that, in the opinion of the investigators, may interfere with the safe conduct, the successful completion, or the quality of the data obtained from the study

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Insulin Resistance
• Metabolic Syndrome
• Metabolic Syndrome X
• Obesity
• Syndrome

Intervention

Behavioral:
• Low-intensity treadmill exercise
Treadmill walking at 30% of VO2Reserve, 3-5 times per week at 20-60 minutes per session, progressive.
• Moderate-intensity treadmill exercise
Treadmill walking at 60% of VO2Reserve, 3-5 times per week at 20-60 minutes per session, progressive.
• Non-aerobic stretching exercise
Floor stretching exercise, 3-5 times per week at 20-60 minutes duration per session, progressive.

Locations

Country	Name	City	State
United States	Charles Drew University of Medicine and Science	Los Angeles	California

Sponsors (2)

Lead Sponsor	Collaborator
Charles Drew University of Medicine and Science	National Center for Research Resources (NCRR)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Insulin sensitivity (clamp)		6 months	No
Secondary	Aerobic fitness (VO2Max, Anaerobic threshold, endurance time)		6 and 12 months	No
Secondary	Body mass index, waist circumference		6 and 12 months	No
Secondary	Fat mass, fat-free mass, lean body mass (DEXA)		6 and 12 months	No
Secondary	Blood pressure		6 and 12 months	No
Secondary	Fasting glucose, hemoglobin A1c, glucose 2 hours post-oral glucose tolerance test, HOMA-IR index		6 and 12 months	No
Secondary	Fasting lipid profile		6 and 12 months	No
Secondary	Apolipoprotein B		6 and 12 months	No
Secondary	Highly-sensitive C-reactive protein		6 and 12 months	No
Secondary	Exercise behavior questionnaire scores		6 and 12 months	No
Secondary	Any adverse events		6 and 12 months	Yes

External Links

•   News item regarding the study. Click here for more information about the study: Dose-Response Effects of Aerobic Exercise on Insulin Resistance and the Metabolic Syndrome