title: Diet and exercise training restore blood pressure and vasodilatory responses during physiological maneuvers in obese children.
abstract: BACKGROUND
  The effects of diet and diet plus exercise training on muscle vasodilatation during physiological maneuvers in obese children are unknown. We tested the hypothesis that (1) blood pressure (BP) and forearm vascular conductance (FVC) responses during handgrip exercise and mental stress would be altered in obese children and (2) diet plus exercise training would restore BP and FVC responses during exercise and mental stress in obese children.
  
  
  RESULTS
  Thirty-nine obese children (aged 10+/-0.2 years) were randomly divided into 2 groups: diet plus exercise training (n=21; body mass index [BMI]=28+/-0.5 kg/m2) and diet (n=18; BMI=30+/-0.4 kg/m2). Ten age-matched lean control children (BMI=17+/-0.5 kg/m2) were also studied. Forearm blood flow was measured by venous occlusion plethysmography. BP was monitored noninvasively. Handgrip exercise was performed at 30% maximal voluntary contraction for 3 minutes. Stroop color word test was performed for 4 minutes. Baseline BP was significantly higher and FVC was significantly lower in obese children. During exercise and mental stress, BP responses were significantly higher and FVC responses were significantly lower in obese children. Diet and diet plus exercise training significantly reduced body weight. Diet and diet plus exercise training significantly decreased BP levels during exercise and mental stress. Diet plus exercise training, in contrast to diet alone, significantly increased FVC responses during exercise (3.7+/-0.3 versus 5.6+/-0.4 U; P=0.01) and mental stress (3.5+/-0.5 versus 4.5+/-0.4 U; P=0.02). After diet plus exercise training, BP and FVC responses during exercise and mental stress were similar between obese children and the control group.
  
  
  CONCLUSIONS
  Obesity exacerbates BP responses and impairs FVC responses during exercise and mental stress in children. Diet and exercise training restore BP and FVC responses in obese children.
authors.affiliation: Department of Endocrinology, Medical School, University of São Paulo, São Paulo, Brazil. mmaltez@usp.br
authors.forename: Maurício M
authors.initials: MM
authors.lastname: Ribeiro
authors.forename: Alexandre G
authors.initials: AG
authors.lastname: Silva
authors.forename: Nelson S
authors.initials: NS
authors.lastname: Santos
authors.forename: Isabel
authors.initials: I
authors.lastname: Guazzelle
authors.forename: Luciana N J
authors.initials: LN
authors.lastname: Matos
authors.forename: Ivani C
authors.initials: IC
authors.lastname: Trombetta
authors.forename: Alfredo
authors.initials: A
authors.lastname: Halpern
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Negrão
authors.forename: Sandra M F
authors.initials: SM
authors.lastname: Villares
mesh_terms: D001794:Blood Pressure; D015992:Body Mass Index; D001835:Body Weight; D002648:Child; D004035:Diet Therapy; D005081:Exercise Therapy; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000098:blood supply; D009765:Obesity / Q000503:physiopathology* / Q000628:therapy*; D010101:Oxygen Consumption; D012039:Regional Blood Flow; D013315:Stress, Psychological / Q000503:physiopathology; D014664:Vasodilation