Exercise alone reduces insulin resistance in obese children independently of changes in body composition.
BACKGROUND
The number of obese children with insulin resistance and type 2 diabetes is increasing, but the best management strategy is not clear.


OBJECTIVE
The objective of this study was to assess the effect of a structured 8-wk exercise training program on insulin resistance and changes in body composition in obese children.


METHODS
The study was 8 wk of structured supervised exercise intervention with outcome measures before and after the exercise period.


METHODS
Fourteen obese children (12.70 +/- 2.32 yr; eight male, six female) with high fasting insulin levels were enrolled into the study.


METHODS
INTERVENTION consisted of 8 wk of supervised circuit-based exercise training, composed of three fully supervised 1-h sessions per week.


METHODS
Outcome measures were assessed pretraining program and posttraining program and included insulin sensitivity (euglycemic-hyperinsulinemic clamp studies), fasting insulin and glucose levels, body composition using dual energy x-ray absorptiometry scan, lipid profile, and liver function tests.


RESULTS
Insulin sensitivity improved significantly after 8 wk of training (M(lbm) 8.20 +/- 3.44 to 10.03 +/- 4.33 mg/kg.min, P < 0.05). Submaximal exercise heart rate responses were significantly lower following the training (P < 0.05), indicating an improvement in cardiorespiratory fitness. Dual energy x-ray absorptiometry scans revealed no differences in lean body mass or abdominal fat mass.


CONCLUSIONS
An 8-wk exercise training program increases insulin sensitivity in obese children, and this improvement occurred in the presence of increased cardiorespiratory fitness but is independent of measurable changes in body composition.
Bell
Lana M
LM
Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, Crawley, Western Australia 6009, Australia.
Watts
Katie
K
Siafarikas
Aris
A
Thompson
Alisha
A
Ratnam
Nirubasini
N
Bulsara
Max
M
Finn
Judith
J
O'Driscoll
Gerry
G
Green
Daniel J
DJ
Jones
Timothy W
TW
Davis
Elizabeth A
EA
D000293:Adolescent; D000886:Anthropometry; D001794:Blood Pressure / Q000502:physiology; D001823:Body Composition / Q000502:physiology*; D002648:Child; D015444:Exercise / Q000502:physiology*; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D009765:Obesity / Q000378:metabolism* / Q000503:physiopathology*; D010809:Physical Fitness / Q000502:physiology
D007328:Insulin