Development of body composition and its relationship with physical activity : A longitudinal study of Swedish children until 4·5 years of age

• In order to develop strategies to prevent early childhood obesity more knowledge about longitudinal body composition development is needed. Previous studies have shown that there is a negative relationship between the physical activity level (PAL) and total body fat (TBF) in children. The aims of this study were: 1) To describe the longitudinal development of body composition from 1 week to 4·5 years of age. 2) To study the relationships between measures of body composition and PAL at 3 years of age. 3) To compare the relationships between body composition measures and PAL at 3 years of age to the corresponding relationships at 1·5 years of age. Body composition was measured using air-displacement plethysmography at 1 week, 12 weeks and at 4·5 years of age. At 1·5 and 3 years body composition and PAL were assessed using the doubly labelled water method and indirect calorimetry. The results showed that TBF% and fat mass index (FMI) were higher than corresponding reference values, during infancy and childhood. We found a relationship between TBF% and PAL at 3 years of age but this was explained by a relationship between PAL and fat-free mass index (FFMI). The corresponding relationship at 1·5 years of age could not be explained by a relationship between PAL and FFMI. In conclusion, the children in this study had higher body fatness compared to the corresponding reference values. This may indicate an identification of a secular trend in body composition development which is characterized by a high body fatness. Our findings also suggest that body fatness might counteract physical activity at 1·5 years of age when the capacity to perform physical activity is limited, however this result was not observed at 3 years of age when such a capacity has been developed.

Ämnesord

LANTBRUKSVETENSKAPER  -- Veterinärmedicin -- Klinisk vetenskap (hsv//swe)

AGRICULTURAL SCIENCES  -- Veterinary Science -- Clinical Science (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Hälsovetenskap -- Folkhälsovetenskap, global hälsa, socialmedicin och epidemiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Health Sciences -- Public Health, Global Health, Social Medicine and Epidemiology (hsv//eng)

Nyckelord

Body composition

energy expenditure

physical activity

children

doubly labelled water

Publikations- och innehållstyp

vet (ämneskategori)

ovr (ämneskategori)