Cardiorespiratory fitness and sedentary activities are associated with adiposity in adolescents.
OBJECTIVE
To determine whether physical activity, sedentary activities, and/or cardiorespiratory fitness are related to waist circumference in adolescents, as previously reported in adults.


METHODS
The study subjects were a representative sample of Spanish adolescents (N = 2859; 1357 boys, 1502 girls; age, 13 to 18.5 years), all of whom were involved in the AVENA (Food and Assessment of the Nutritional Status of Adolescents) study. BMI, waist circumference, pubertal maturation status, and cardiorespiratory fitness were measured in all. Leisure-time physical activity, sedentary activities, active commuting to school, and socioeconomic status were assessed by self-reported questionnaires.


RESULTS
No relationship was found between leisure-time physical activity and BMI or waist circumference. In contrast, and in both boys and girls and after adjustment for confounding variables, cardiorespiratory fitness was found to be inversely associated with waist circumference and BMI, independent of sedentary activities or physical activity (p < or = 0.001). The maximum oxygen consumption explained 13% of the variance in waist circumference in boys and 16% in girls. Sedentary activities were independently and directly related to waist circumference in both boys and girls (p < or = 0.05) and to BMI in boys (p < or = 0.05). Sedentary activities explained 10% of the variance in waist circumference in boys and 18% in girls. The BMI-adjusted waist circumference was inversely correlated with cardiorespiratory fitness in overweight-obese boys (p < or = 0.05) and showed a trend toward significance in girls (p < or = 0.1).


CONCLUSIONS
Both moderate to high levels of cardiorespiratory fitness and sedentary activities, but not physical activity, are associated with lower abdominal adiposity, as measured by waist circumference.
Ortega
Francisco B
FB
Department of Medical Physiology, School of Medicine, University of Granada, Granada 18071, Spain. ortegaf@ugr.es
Tresaco
Beatriz
B
Ruiz
Jonatan R
JR
Moreno
Luis A
LA
Martin-Matillas
Miguel
M
Mesa
Jose L
JL
Warnberg
Julia
J
Bueno
Manuel
M
Tercedor
Pablo
P
Gutiérrez
Angel
A
Castillo
Manuel J
MJ
D050154:Adiposity / Q000502:physiology*; D000293:Adolescent; D015992:Body Mass Index; D002320:Cardiovascular Physiological Phenomena; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007899:Leisure Activities; D008168:Lung / Q000502:physiology*; D008176:Lung Volume Measurements; D008297:Male; D010809:Physical Fitness; D049629:Waist-Hip Ratio