Socio-economic status, growth, physical activity and fitness: the Madeira Growth Study.
BACKGROUND
Within a country social conditions change over time and these conditions vary from country to country. The associations between these conditions, somatic growth, physical activity and fitness reflect these changes.


OBJECTIVE
The study documented variation in somatic growth, physical activity and fitness associated with socio-economic status (SES).


METHODS
The study involved 507 subjects (256 boys and 251 girls) from the Madeira Growth Study, a mixed longitudinal study of five cohorts (8, 10, 12, 14 and 16 years of age) followed at yearly intervals over 3 years (1996-1998). A total of 1493 observations were made. Anthropometric measurements included lengths, body mass, skeletal breadths, girths and skinfolds. Physical activity and SES were collected via questionnaire and interview. Physical fitness was assessed using the Eurofit test battery. Variation in somatic growth, physical activity and physical fitness by SES (high, average and low) was tested with analysis of variance.


RESULTS
Significant differences between SES groups were observed for height, body mass and skinfolds. Boys and girls from high SES groups were taller, heavier and fatter (subscapular and triceps skinfolds) than their peers from average and low SES groups. At some age intervals, the high SES group had larger skeletal breadths (girls) and girths (boys and girls) than low SES. Small SES differences were observed for physical activity (sport and leisure-time indices). SES was significantly associated with physical fitness. At some age levels, boys from the low SES group performed better for muscular and aerobic endurance whereas girls from the high SES group performed better for power.


CONCLUSIONS
Considerable variation in somatic growth and physical fitness in association with SES has been demonstrated, but little association was found for physical activity.
Freitas
Duarte
D
Department of Physical Education and Sports, University of Madeira, Funchal, Portugal. dfreitas@uma.pt
Maia
José
J
Beunen
Gaston
G
Claessens
Albrecht
A
Thomis
Martine
M
Marques
Antonio
A
Crespo
Maria
M
Lefevre
Johan
J
D000293:Adolescent; D000367:Age Factors; D001837:Body Weights and Measures; D002648:Child; D015331:Cohort Studies; D005260:Female; D006128:Growth; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010809:Physical Fitness; D011174:Portugal / Q000453:epidemiology; D012959:Socioeconomic Factors