OBESITY INDICATORS AND ATHLETIC PERFORMANCE IN 11-15 YEAR-OLD CHILDREN

Poveæana tjelesna masa djece se često u literaturi povezuje sa smanjenim sposobnostima vezanima uz sportsku izvedbu. Zbog smanjenih motoričkih sposobnosti takva djeca često izbjegavaju sudjelovanje u sportskim aktivnostima što dovodi do zatvorenog kruga tj. do daljnjeg povećanja tjelesne mase. Cilj ovog rada bio je utvrditi koje motoričke sposobnosti su pod najvećim utjecajem povećane tjelesne mase, te da li postoje razlike prema spolu. Uzorak se sastojao od 224 djece koji su bili polaznici 5, 6, 7 i 8-og razreda osnovne škole (prosječna dob 13,07±1,24). Prije početka istraživanja, detaljna objašnjenja postupka ispitivanja te obrazac za suglasnost roditelja poslana su roditeljima djece. Protokol testiranja je obuhvaćao mjerenje morfoloških karakteristika (visina, težina, postotak masti) i različitih motoričkih sposobnosti (brzina, snaga, vrijeme reakcije, ravnoteža mjereni na Kistler Quattro jump force platformi, ravnotežnim platformama i Newtest Powertimer PC sustavu). Za svako dijete je izračunat indeks tjelesne mase i postotak masti, te je pojedinačno svaki ispitanik uvršten u pojedinu skupinu prema stupnju uhranjenosti (nedovoljno uhranjeni, normalno uhranjeni, poveæane tjelesne mase i pretili). U tu svrhu su se koristili grafikoni rasta za dob i spol. ANOVA/MANOVA statistička analiza je ukazala na znaèajan pad sposobnosti s porastom stupnja uhranjenosti u svim motoričkim testovima osim testovima ravnoteže kod dječaka. Nasuprot tome, neočekivano, sposobnosti djevojaka većeg indeksa tjelesne mase se nisu značajno razlikovale od onih nižeg indeksa. Jedini statistički značajno lošiji rezultat deblje djevojke su postigle na testu repetitivnih pokreta donjih ekstremiteta. U zaključku, sportski programi koji se nude u školama morali bi sadržavati i aktivnosti u kojima se dječaci povećane tjelesne mase neće osjećati nedovoljno sposobnima, a možda čak i neke sportove u kojima je bitna ravnoteža kao pokazatelj koji je najmanje pod utjecajem tjelesne mase kao npr. skateboard i sl.An increased body mass in children is usually associated with a decrease in athletic performance. Because of the poorer performance, children tend to avoid the participation in sport activities. This leads to the vicious circle resulting in further increase in body weight. The aim of this study was to identify the motor abilities which are most affected by the body mass increase and to investigate the possible differences in the influence of body mass index on motor abilities with regard to sex. The sample comprised 224 children attending 5th, 6th , 7th and 8th grade of the elementary school (mean age 13,07±1,24). Prior to testing, the detailed explanations of the testing procedure as well as the parental consent form were distributed to the parents. The children underwent testing procedure encompassing measurements of morphological characteristics (height, weight, body fat percentage) and motor abilities (various tests for speed, power, reaction time and balance performed on Kistler Quattro jump force platform, balance boards or Newtest Powertimer PC system). For each child the body fat percentage and body mass index were calculated. Each subject was checked on percentile growth chart for children and classified into one of four categories: underweight, normal weight, overweight or obese. The ANOVA/MANOVA analysis showed, in boys, a significant decrease in all tested motor abilities with the increase of body weight except for the balance board performance. On the contrary, the athletic performance in girls was not significantly influenced by the increase of body mass index. The only test in which the decrease in performance in girls was noted was the test measuring the frequency of lower legs repetitive movements. In conclusion, as the overweight boys of that age do not perform in sport activities as good as their leaner counterparts do, we think that a special attention should be paid to the selection of the sport activities offered for boys in school sport clubs. We have seen here that the balance is still well preserved, regardless of the body mass, so it might be a good choice to offer skateboard classes or similar activities