Effects of exercise training and its cessation on components of the insulin resistance syndrome in obese children.
OBJECTIVE
To determine the effect of exercise training (ET) on components of the insulin resistance syndrome (IRS) in obese children.


METHODS
Randomized, modified cross-over study, with subjects assigned to one of two conditions: (1) 4 months of ET followed by 4 months of no-ET; or (2) 4 months of no-ET followed by 4 months of ET. Measurements were made at three time points: 0, 4 and 8 months.


METHODS
79 obese, but otherwise healthy children (age: 7-11 y, percent fat (%fat) 27-61%).


METHODS
Plasma lipid and lipoprotein concentrations, plasma insulin and glucose concentrations; %fat; submaximal heart rate (HR) as an index of fitness. EXERCISE TRAINING: ET was offered 5 d/week 40 min/d. For the 73 children who completed 4 months of ET, the mean attendance was 80% (that is, 4 d/week) and the average HR during ET was 157 bpm.


RESULTS
Significant (P < 0.05) group x time interactions were found for plasma triglyceride (TG) and insulin concentrations and %fat. The average change for both groups, from just before ET to just after the 4 month ET was -0.24 mmol.l-1 for TG, -25.4 pmol.l-1 for insulin and -1.6 units for %fat. When Group 1 ceased ET, over the following 4 month period the average change for insulin was +26.6 pmol.l-1 and for %fat +1.3 units.


CONCLUSIONS
Some components (plasma TG, insulin, %fat) of the IRS are improved as a result of 4 months of ET in obese children. However, the benefits of ET are lost when obese children become less active.
Ferguson
M A
MA
Georgia Prevention Institute, Department of Pediatrics, Medical College of Georgia, Augusta 30912-3710, USA.
Gutin
B
B
Le
N A
NA
Karp
W
W
Litaker
M
M
Humphries
M
M
Okuyama
T
T
Riggs
S
S
Owens
S
S
D000704:Analysis of Variance; D001823:Body Composition; D002648:Child; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D018592:Cross-Over Studies; D004032:Diet; D015444:Exercise; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male; D009765:Obesity / Q000378:metabolism / Q000628:therapy*; D014280:Triglycerides / Q000097:blood
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D007328:Insulin; D014280:Triglycerides