Ten months of exercise improves general and visceral adiposity, bone, and fitness in black girls.
OBJECTIVE
The goal of this study was to evaluate the impact of a 10-month after-school physical activity (PA) program on body composition and cardiovascular (CV) fitness in young black girls.


METHODS
Subjects were 8- to 12-year-olds recruited from elementary schools. Body composition was measured using anthropometrics {waist circumference and BMI, DXA [percentage body fat (%BF)] and bone mineral density (BMD)}, and magnetic resonance imaging [visceral adipose tissue (VAT)]. CV fitness was measured using a graded treadmill test. The intervention consisted of 30 minutes homework/healthy snack time and 80 minutes PA (i.e., 25 minutes skills instruction, 35 minutes aerobic PA, and 20 minutes strengthening/stretching). Analyses were adjusted for age, baseline value of the dependent variable, and sexual maturation (pediatrician observation).


RESULTS
Mean attendance was 54%. Compared with the control group, the intervention group had a relative decrease in %BF (p < 0.0001), BMI (p < 0.01), and VAT (p < 0.01) and a relative increase in BMD (p < 0.0001) and CV fitness (p < 0.05). Higher attendance was associated with greater increases in BMD (p < 0.05) and greater decreases in %BF (p < 0.01) and BMI (p < 0.05). Higher heart rate during PA was associated with greater increases in BMD (p < 0.05) and greater decreases in %BF (p < 0.005).


CONCLUSIONS
An after-school PA program can lead to beneficial changes in body composition and CV fitness in young black girls. It is noteworthy that the control and intervention groups differed in change in VAT but not waist circumference. This suggests that changes in central adiposity can occur in response to PA, even in young children, but that waist circumference may not be a good indicator of central adiposity.
Barbeau
Paule
P
Department of Pediatrics, Medical College of Georgia, Georgia Prevention Institute, 1499 Walton Way, HS1755, Augusta, GA 30912, USA. pbarbeau@mcg.edu
Johnson
Maribeth H
MH
Howe
Cheryl A
CA
Allison
Jerry
J
Davis
Catherine L
CL
Gutin
Bernard
B
Lemmon
Christian R
CR
D015502:Absorptiometry, Photon; D001741:Black or African American; D001823:Body Composition / Q000502:physiology; D015519:Bone Density / Q000502:physiology*; D002648:Child; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D050152:Intra-Abdominal Fat / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology; D010809:Physical Fitness / Q000502:physiology*; D018709:Statistics, Nonparametric