Childhood obesity is a leading public health concern because overweight youth suffer from co-morbidities such as insulin resistance, type 2 diabetes mellitus (T2DM), metabolic syndrome and cardiovascular disease, conditions once considered unique to adults. Although the causes of childhood obesity are not clear, decreased physical activity (PA) is a major factor. In adults, it is well established that regular PA (>150 min/wk) or 30 min/day of PA for 5-7 days/wk is associated with significant reductions in adiposity and prevention of T2DM. However, the potential benefits of this level of PA alone (without calorie restriction) on abdominal obesity, ectopic fat and risk factors for T2DM are unclear in overweight girls. Therefore, we will examine the effects of regular exercise without calorie restriction in overweight girls on: 1) in vivo insulin sensitivity and secretion and risk of T2DM using the clamp technique;2) total and abdominal adiposity using whole body magnetic resonance imaging;3) ectopic fat in the liver and skeletal muscle using 1H-magnetic resonance spectroscopy. More specifically, we will compare the effects of different exercise modalities (aerobic exercise versus resistance exercise) on these health markers, and explore the potential mechanisms by which regular exercise mediates improvements in health risks associated with T2DM. We will recruit 42 sedentary overweight black and white girls, and randomly assign them to one of three 3-month intervention groups: aerobic training (180 min per week), resistance training (180 min per week), or no-exercise control. We believe that the results of this study will be of significance for the development of evidence-based public health and clinical guidelines in our efforts to combat the current epidemic of childhood obesity.

Public Health Relevance

We will examine the effect of a 3-month exercise training (aerobic exercise versus resistance exercise) without dieting on obesity reduction, and improving fitness, body composition and risk of type 2 diabetes in overweight black and white girls.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21DK083654-02
Application #
8106083
Study Section
Special Emphasis Panel (ZRG1-EMNR-K (90))
Program Officer
Linder, Barbara
Project Start
2010-07-15
Project End
2013-06-30
Budget Start
2011-07-01
Budget End
2013-06-30
Support Year
2
Fiscal Year
2011
Total Cost
$181,602
Indirect Cost
Name
University of Pittsburgh
Department
Pediatrics
Type
Schools of Medicine
DUNS #
004514360
City
Pittsburgh
State
PA
Country
United States
Zip Code
15213
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Lee, SoJung; Rivera-Vega, Michelle; Alsayed, Hany Mohamed Abdel Aal et al. (2015) Metabolic inflexibility and insulin resistance in obese adolescents with non-alcoholic fatty liver disease. Pediatr Diabetes 16:211-8
Lee, SoJung; Deldin, Anthony R; White, David et al. (2013) Aerobic exercise but not resistance exercise reduces intrahepatic lipid content and visceral fat and improves insulin sensitivity in obese adolescent girls: a randomized controlled trial. Am J Physiol Endocrinol Metab 305:E1222-9
Rajakumar, Kumaravel; de las Heras, Javier; Chen, Tai C et al. (2011) Vitamin D status, adiposity, and lipids in black American and Caucasian children. J Clin Endocrinol Metab 96:1560-7
George, Lindsey; Bacha, Fida; Lee, Sojung et al. (2011) Surrogate estimates of insulin sensitivity in obese youth along the spectrum of glucose tolerance from normal to prediabetes to diabetes. J Clin Endocrinol Metab 96:2136-45
Tfayli, Hala; Lee, So Jung; Bacha, Fida et al. (2011) One-hour plasma glucose concentration during the OGTT: what does it tell about ?-cell function relative to insulin sensitivity in overweight/obese children? Pediatr Diabetes 12:572-9
Tfayli, Hala; Ulnach, Julia Warren; Lee, SoJung et al. (2011) Drospirenone/ethinyl estradiol versus rosiglitazone treatment in overweight adolescents with polycystic ovary syndrome: comparison of metabolic, hormonal, and cardiovascular risk factors. J Clin Endocrinol Metab 96:1311-9
Lee, SoJung; Kuk, Jennifer L; Kim, YoonMyung et al. (2011) Measurement site of visceral adipose tissue and prediction of metabolic syndrome in youth. Pediatr Diabetes 12:250-7
Tfayli, Hala; Lee, SoJung; Arslanian, Silva (2010) Declining beta-cell function relative to insulin sensitivity with increasing fasting glucose levels in the nondiabetic range in children. Diabetes Care 33:2024-30
Bacha, Fida; Lee, Sojung; Gungor, Neslihan et al. (2010) From pre-diabetes to type 2 diabetes in obese youth: pathophysiological characteristics along the spectrum of glucose dysregulation. Diabetes Care 33:2225-31