Martine A. DEIGHAN, Alan M. NEVILL, Nicola MAFFULLI, Jack C. Y. CHENG, Nigel GLEESON

Atletik ve sedanter çocuklarda diz zirve torkunun değerlendirilmesi

Amaç: Çalışmada, alometrik model yaklaşımı kullanılarak, çocuklarda cinsiyet, aktivite düzeyi ve pubertal durumun diz ekstansiyon ve ﬂeksiyonundaki zirve torku üzerindeki etkisi incelendi. Çalışma planı: Çalışmaya Hong Kong ortaokuluna devam etmekte olan, 12-13 yaşlarında 140 öğrenci (67 erkek, 73 kız) alındı. Öğrencilerin 69’u beden eğitimi ağırlıklı, 71’i sanat ağırlıklı dersler görmekteydi. Tüm öğrencilerde baskın bacakta izokinetik konsantrik ekstansiyon ve ﬂeksiyonda zirve torku Cybex II + dinamometre ile 1.04 rad/saniyede ölçüldü; beden kütlesi, boy ve pubertal evreleri belirlendi. Mutlak zirve torku değerleri ile, kas hareketini (ekstansiyon ve ﬂeksiyon) grup içi faktör ve gruplararası faktör olarak ele alan, cinsiyet, grup ve pubertal evrenin de katıldığı tekrarlı ölçümlerde ANOVA testi yapıldı. Beden ölçüsüne göre ayarlı zirve torkunun etkilerini değerlendirmek için, beden kütlesi ve uzunluğun eşdeğişken olarak alındığı lineer ANCOVA ve log-lineer ANCOVA teknikleri kullanıldı. Sonuçlar: Zirve torku değerleri erkeklerde kızlara göre, beden eğitimi grubunda sanat dersleri grubuna göre anlamlı derecede yüksek bulundu. Zirve torku beden ölçüsündeki farklılıklara göre ayarlandığında, iki grupta kızlar arasında, erkeklere göre zirve torku daha fazla farklılık gösterdi ve pubertal evrenin bu farklılıkta anlamlı bir etkisi vardı. Alometrik analizde zirve torkunun beden kütlesine göre uzunluktan daha fazla etkilendiği ve vücut ölçülerine kıyasla daha büyük oranda artış gösterdiği görüldü (p

Anahtar Kelimeler:

Antropometri, Buluğ çağı, Çocuk gelişimi, Vücut boyu, Ergen, Egzersiz, Cinsiyet faktörleri, Tork, Varyans analizi, Vücut ağırlığı, İzometrik kasılma

Evaluation of knee peak torque in athletic and sedentary children

Objectives: We examined the inﬂuence of sex, level of activity, and pubertal status on knee extension (Ext) and ﬂexion (Fl) peak torque (PT) in children using an allometric modeling approach. Methods: A total of 140 students (67 males, 73 females) aged 12/13 years were enrolled from a Hong Kong junior high school, whose curricula were based on physical education (n=69) or arts (n=71). Isokinetic concentric Ext and Fl PT of the dominant leg was assessed at 1.04 rad/sec using a Cybex II + dynamometer and body mass, stature, and pubertal stage were measured. A repeatedmeasures ANOVA test was performed on absolute PT data with muscle action (Ext and Fl) as a within-subject factor and between-subject factors including sex, group, and pubertal stage. To assess the effects on body sizeadjusted PT, linear ANCOVA and log-linear ANCOVA techniques were used with body mass and stature taken as covariates. Results: Peak torque was signiﬁcantly greater in boys compared to girls, and in the physical education group compared to the arts group. When PT was adjusted for differences in body size, there was a greater difference in PT between girls in the two groups compared to boys, and there was a signiﬁcant effect of pubertal stage. Allometric analysis showed that PT was inﬂuenced more by stature than body mass, and PT increased at a greater rate than body size (both p<0.01). Conclusion: There may be a need for a physical activity intervention in sedentary 12/13 year old girls. Peak torque appears to increase disproportionately to body size. This may result from a greater increase in leg muscle mass relative to body mass.

Keywords:

Anthropometry, Puberty, Child Development, Body Height, Adolescent, Exercise, Sex Factors, Torque, Analysis of Variance, Body Weight, Isometric Contraction,

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