Abstract des Autors

Purpose: This study was a longitudinal examination of the change in both the activities done and the intensity of those activities from childhood to adolescence. Methods: Common activities were assessed by questionnaire initially on 656 subjects from 21 elementary schools; 50.5% were female, 83.4% were Caucasian, 20.6% African-American, and 6.0% were other races. Results: Girls more often reported sedentary activities overall. Weighted least squares analyses showed boys consistently reported more vigorous activities than girls (P<0.0008). African-American girls reported fewer vigorous activities than Caucasian or other race girls (P=0.027). Sedentary activities were more frequently reported with increasing age (chi-square P<0.001). The youngest African-American and Caucasian boys reported similar activity patterns. However, boys from other races reported more intense activities until sixth and seventh grades when African-American boys began reporting more sedentary activities than Caucasians or other races (P=0.004). During sixth-eighth grades, Generalized Estimating Equations (GEE) models show that girls with more advanced pubertal status reported more sedentary activities than girls who were less developed (P<0.0001). For high school girls, race was a marginally significant predictor (P=0.05) of activity status. Neither race nor pubertal status were significant factors in activities chosen by middle school boys. However, for male high school students, Caucasians were more likely than African-Americans to report vigorous activities (P=0.005). Conclusions: Variation in activities by race within gender suggests that establishing activity patterns in youth may be race-specific as well as gender-specific and must be accounted for in designing physical activity interventions. Also, pubertal maturation is a factor in activity choices in middle school girls. Verf.-Referat