Diet and exercise training in obese children

Ribeiro MM et al. (2005) Diet and exercise training restore blood pressure and vasodilatory responses during physiological maneuvers in obese children. Circulation 111: 1915–1923

The increasing prevalence of childhood obesity has stimulated new research into its implications and treatment. A new study from Brazil has investigated the effects of diet and exercise on muscle vasodilatory responses and blood pressure in a group of obese children.

Thirty-nine consecutive outpatients aged 8–12 years, with a mean BMI of 29 ± 0.3 kg/m², were randomized to a regimen of diet plus exercise (n = 21) or to diet alone (n = 18). Also included were 10 age-matched control children with a mean BMI of 17 ± 0.5 kg/m².

At baseline, the obese children had significantly higher mean blood pressure than their lean counterparts; furthermore, forearm vascular conductance responses—measured during handgrip exercises and mental stress—were significantly lower in the obese group.

In addition to producing significant weight loss in the obese patients, the diet regimen was associated with decreased blood pressure during the exercise and mental stress testing. In those following the diet plus exercise regimen, blood pressure and forearm vascular conductance responses were similar to those measured in the lean children.

In summary, the study shows that obesity affects blood pressure and forearm vascular conductance responses during exercise and mental stress testing, and that diet and exercise can normalize these responses.