Everyday physical activity and adiposity in Prader-Willi syndrome.

The aim of this study was to assess the impact of Prader-Willi syndrome (PWS) on the level of everyday physical activity and to explore whether the activity level is related to adiposity. Measurements were performed with an accelerometry-based Activity Monitor during two consecutive schooldays in 12 children with PWS (7-16 years of age) and in 12 age- and gender-matched, healthy children. Adiposity was assessed by body mass index standard deviation scores and by percentage body fat (dual energy X-ray absorptiometry). Mean duration of dynamic activities (expressed as percentage of 24 h) was lower in children with PWS than in the comparison group (8.7 [2.5]% and 12.0 [3.1]%, respectively; p = 0.01). Six children with PWS had normal activity levels. Physical activity level was not related to adiposity. The results indicate that, as a group, children with PWS have an inactive lifestyle. However, children with PWS cannot be stereotyped as inactive since half of them had normal activity levels.