Effects of exercise training and its cessation on components of the insulin resistance syndrome in obese children

Int J Obes Relat Metab Disord. 1999 Aug;23(8):889-95. doi: 10.1038/sj.ijo.0800968.


Objective: To determine the effect of exercise training (ET) on components of the insulin resistance syndrome (IRS) in obese children.

Design: 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.

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

Measurements: 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.

Conclusion: 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.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Analysis of Variance
  • Body Composition
  • Child
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Cross-Over Studies
  • Diet
  • Exercise*
  • Female
  • Humans
  • Insulin / blood
  • Insulin Resistance*
  • Male
  • Obesity / metabolism
  • Obesity / therapy*
  • Triglycerides / blood


  • Cholesterol, HDL
  • Cholesterol, LDL
  • Insulin
  • Triglycerides