GROWTH, WEIGHT STATUS AND MOTOR PERFORMANCE IN ITALIAN PRIMARY SCHOOL CHILDREN

The predominant sedentary lifestyle of the present child population involves a reduction of the motor capacities and variations of the weight status. The aim of this study was to assess the relationships between motor performance and weight status in primary school children from Bologna (Emilia Romagna, Italy). The body weight (BW) and height (H) was assessed in 717 children (M: 368; F: 349), aged 6 to 11 yrs. The weight status was classified according to cut offs proposed by Cole et al. (2007). All the children performed then 8 motor tests: Handgrip Test for Maximal Isometric Strength (HG), Sit and Reach (SR), Dynamic Balance Test (DBT), Eye-hand Coordination Test (ECT), Standing Long Jump (SLJ), Upper Limb Explosive Strength Test (UST), Dotting Test (DT), Comma Test (CT). Three way Analysis of Variance (ANOVA) was used to analyze the differences in each test performance between genders, age groups (6,7,8,9,10,11 yrs), and weight status groups (underweight, normal-weight, overweight). Gender differences have been found in 7 out of 8 tests. Overweight children performed better than the other groups in 2 strength tests and worse in 1 strength test, whereas no differences were observed in the coordination ability test between the normal-weight and underweighted children. Normal-weight children performed better only in 1 test out of 8. Generally the score of the tests showed a trend to improve with increasing age. Some tests showed a trend to stabilize at the age of 8 and 9. The results showed that overweight children were disadvantaged in activities where the subject is engaged to develop force against gravity. Conversely, in static tests where it is not demanded an action against gravity; the overweight children show better performances. Normally the males perform better compared to females, with the exception of the SR test, and in CT, where greater precision and executive rhythm are required. The results suggest the presence of a sensible phase, for given capacities, up to 7-8 yrs and, in a less extent, in the following years. It is worth noting the different outcome of the strength capacity: the upper limbs explosive strength shows a constant increase up to 10 years, whereas for the lower limb strength and the maximum isometric strength, the increasing trend seems to restart after the stabilization in the 8-9 yrs class . These outcomes, if confirmed by the longitudinal study, will allow more precise interpretations of the interrelationships between somatic growth, weight status and motor performance. In static or segmental activities, obese children show similar performances compared to normal-weight children. This supports the idea that, for overweight and obese children, motor programs involving dynamic activities and whole-body displacement are needed. This kind of activities should stimulate appreciable energy consumption and facilitate weight loss. Parents and educators have to consider these indications to entice the children to practice, in the extra-school time, simple activities involving high energy consumption such as walking, running, and cycling.