47 REV MED UNIV NAVARRA/VOL. 46, Nº 1, 2002, 53-56 53 RESÚM ENES DE TRABAJOS PUBLI CADOS EN OTRAS REVI STAS RESÚM ENES DE TRABAJOS PUBLI CADOS EN OTRAS REVI STAS Abstract of: lnt J Obes Relat Metab Disord 1999 Nov;23(11):1192-201 Background: Diverging trends of decreasing energy intake and increasing prevalence of obesity suggest that physical inac- tivity and sedentary lifestyle may be one of the key determi- nants of the growing rates of overweight/obesity in Western populations information about the impact of physical inactivi- ty and sedentary lifestyles on the prevalence of obesity among the general adult population in the European Union is sparse. Objectives: To estimate the association of leisure-time seden- tary and non-sedentary activities with body mass index (BMI, kg/m2) and with the prevalence of obesity (BMI> 30 kg/m2) in a sample of the 1 5 member states of the European Union. Methods: Professional interviewers administered standardized in-home questionnaires to 15.239 men and women aged 15 years upwards, selected by a multi-stage stratified cluster sam- pling with quotas applied to ensure national and European rep- resentativeness. Energy expenditure during leisure time was calculated based on data on frequency of and amount of time participating in various physical activities, assigning metabolic equivalents (METS) to each activity. Sedentary lifestyle was assessed by means of self-reported hours spent sitting down during leisure time. Multiple linear regression models with BMI as the dependent variable, and logistic regression models with obesity (BMI> 30 kg/m2) as the outcome, were fitted. Results: Independent associations of leisure-time physical activ- ity (inverse) and amount of time spent sitting down (direct) with BMI were found. The adjusted prevalence odds ratio (OR) for obesity was 0.52 [95% confidence interval (01): 0.43-0.64, P< 0.001] for the upper quintile of physical activity (> 30 METS) compared with the most physically inactive quintile (< 1 .75 METS). A positive independent association was also evident for the time spent sit- ting down, with an adjusted OR= 1.61 (95% 01: 1.33-1.95, P< 0.001) for those who spent more than 35 h of their leisure time sitting down compared with those who spent less than 15 h. Conclusions: Obesity and higher body weight are strongly associated with a sedentary lifestyle and lack of physical activi- ty in the adult population of the European Union. These results, however, need to be interpreted with caution due to the cross- sectional design. Nonetheless, they are consistent with the view that a reduction in energy expenditure during leisure time may be the main determinant of the current epidemic of obesity. Pysical inactivity, sedentary lifestyle and obesity in the European Union M.A. Martínez-González, J.A. Martínez, F.B. Hu, M.J. Gibney, J. Kearney Abstract of: Journal of Pediatric Orthopaedics- Part B 2001;10:334-8 We study the morphological effect of low, mechanical stresses (compression, tension and neutralization) on the growth carti- lage with an external fixator in 18 young lambs. In the radiogra- phy we only found more length in the femora subjected to ten- sion (p< 0.05). Bony bridges were not present, nor were there signs of altered vascularization or Ranvier's perichondral ring. Histomorphometrically, in the group subjected to tension, the germinative layer in the femur was higher (p< 0.001) in the bones which had undergone surgery. The proliferative layer were lower in the operated tibia (p< 0.001) and the hyper- trophic layer were higher in operated tibias and femora (p< 0.001). In the group subjected to compression, the germinative layer in the femora were higher in the operated bones (p< 0.05); the proliferative layer of the tibia was lower (p< 0.001) and the hypertrophic layer were higher (p< 0.001) in both operated bones. In the neutralization group, the proliferative layer of both oper- ated bones presented lower values (p< 0.001) and the hyper- trophic layer was heigher (p< 0.001) than the control groups. Histomorphometric study of growth plate subjected to different mechanical conditions (compression, tension and neutralization). An experimental study in lambs Arriola F, Forriol F, Cafladell J. Orthopaedic Research Laboratory, School of Medicine, University of Navarra