GET FIT: Glycemic Load & Resistance Training on Endothelial Function & Insulin Sensitivity

Sponsor

University of California, Los Angeles (Other)

Overall Status

Completed

CT.gov ID

NCT01755962

Collaborator

(none)

Enrollment

Location

Arms

68.4

Duration (Months)

1.3

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

This project is prompted by the urgent public health need to identify novel strategies to prevent cardiovascular disease (CVD) and type 2 diabetes (T2D). The higher prevalence of CVD, T2D, and metabolic syndrome in obese individuals is a major healthcare concern. Therefore, finding optimal intervention strategies to combat these growing epidemics is imperative.

Condition or Disease	Intervention/Treatment	Phase
160 Participants Aged 18-35 Years and Obese (BMI ≥30) Open to Men and Women of All Ethnicity	Other: Glycemic Load Other: Resistance Training	N/A

Detailed Description

At present, the extent to which dietary components can modify endothelial function, monocyte inflammation and glycemic variations is not well defined, although different carbohydrates are known to vary in their abilities to induce plasma glucose and insulin responses. Epidemiologic work suggests that high dietary glycemic load (GL) is associated with increased concentrations of inflammatory cytokines, endothelial dysfunction markers, and increased risk of T2D and coronary heart disease (CHD). We are examining using randomized control trials low vs. high-GL diet to determine if low-GL diets induce improvements in endothelial function or monocyte inflammation. Furthermore, resistance training is an alternate form of exercise from conventional aerobic training. Resistance Training has the potential to improve endothelial function or monocyte phenotype, but there is very little data in this area. We hypothesize that resistance training may augment the beneficial effects of a low-GL diet in improving metabolic health.

Study Design

Study Type:

Interventional

Actual Enrollment :

88 participants

Allocation:

Randomized

Intervention Model:

Factorial Assignment

Intervention Model Description:

There are four intervention arms designed to compare two factors, glycemic load and resistance training. Arms consist of high glycemic diet, no exercise, high glycemic diet, resistance training; low glycemic diet, no exercise; low glycemic diet, resistance training.There are four intervention arms designed to compare two factors, glycemic load and resistance training. Arms consist of high glycemic diet, no exercise, high glycemic diet, resistance training; low glycemic diet, no exercise; low glycemic diet, resistance training.

Masking:

None (Open Label)

Primary Purpose:

Treatment

Official Title:

Glycemic Load & Resistance Training on Endothelial Function & Insulin Sensitivity

Study Start Date :

Apr 1, 2012

Actual Primary Completion Date :

Dec 14, 2017

Actual Study Completion Date :

Dec 14, 2017

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Low Glycemic Load + Resistance Training 12-week intervention diet + resistance training (1 hour, 3 times per week)	Other: Glycemic Load Other: Resistance Training
Experimental: High Glycemic Load + Resistance Training 12-week control diet + resistance training (1 hour, 3 times per week)	Other: Glycemic Load Other: Resistance Training
Experimental: Low Glycemic Load 12-week intervention diet	Other: Glycemic Load
Other: High Glycemic Load 12-week control diet	Other: Glycemic Load

Outcome Measures

Primary Outcome Measures

Endothelial function as determined by brachial artery FMD [12 weeks]

Secondary Outcome Measures

monocyte inflammation [12 weeks]
Insulin Sensitivity by Oral Glucose Tolerance Test [12 weeks]
MAGE via Continuous Glucose Monitoring System [12 weeks]

Other Outcome Measures

body composition (total fat mass, visceral fat, HFF, LBM) via DXA and MRI [12 weeks]
plasma and cellular biomarkers post pre and post 12 week intervention [12 weeks]
Monocytes will be isolated from subject whole blood and will be phenotyped in 2 ways: 1) as pro- or anti-inflammatory based on flow-activated cell sorting (FACS) analysis of monocyte-specific markers TLR-4, CD14 and CD16. Serum-Stimulated Cell Culture. Subject serum will be incubated with L6 cells as we have previously performed in monocytes and adipocytes as well as endothelial cells 18, 130. Following 48 hr incubation, cellular insulin-stimulated glucose transport will be assayed as described 129 and conditioned medium assayed for myokine levels (ex. IL-15, 1L-6, etc). Fasting plasma (and conditioned media where appropriate) will be taken to determine a panel of adipokines and hormones (e.g. insulin, adiponectin, HSP-72, IL-4, IL-6, IL-10, MCP-1, CRP, 8-iso PGF2α) will be measured using the Millipore Multiplex assay kit or with specific ELISA kits
RNA/protein levels via muscle and fat tissue collection [12 weeks]
Approximately 300 mg of muscle tissue from the superficial portion of the vastus lateralis and approximately 3-5 g of subcutaneous adipose tissue from the periumbilical portion of the abdomen will be obtained.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 35 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

18-35 with BMI≥30 and/or your waist circumference ≥40 inches for males or ≥35 inches for females
In good health as determined by the screening visit and review of medical history

Exclusion Criteria:

Have a known heart arrhythmia and/or abnormalities found in electrocardiogram (ECG) reading or use of medications that influence CV function
Have been in a weight loss or exercise program in the 6 months prior to participation
Use tobacco products
Have a syndrome or are prescribed medications that may influence body composition, insulin action, or CVD (e.g. PCOS, prednisone, methylphenidate, etc.)
Have intolerance to lactose or gluten
Pregnant