The purpose of this study was to assess differences in the levels of plasma visfatin among female adolescents and changes in plasma visfatin and insulin resistance in obese female adolescents after 12 wk of aerobic exercise training. Twenty normal-weight female students (body-mass index [BMI] <22.9 kg/m2 and body fat ≤29.9) and 18 obese female students (BMI ≥25 kg/m2 and body fat ≥30%) participated in this study. Eleven obese students were assigned to an exercise group and completed a 12-wk aerobic exercise-training program that included four 40- to 50-min sessions per wk with an energy expenditure of 300–400 kcal/d. Seven obese students were assigned to a control group that received no exercise sessions or dietary restriction. The plasma visfatin levels of obese female adolescents were significantly higher (p < .05) than those of the normal-weight female adolescents. The plasma visfatin levels (294.00 ± 124.74 ng/ml to 185.55 ± 67.30 ng/ml, p < .01) and insulin resistance (p < .05) were significantly reduced after 12 wk of aerobic exercise. The results suggest that aerobic exercise resulting in an energy expenditure of 1,200–1,600 kcal/wk for 12 wk decreases plasma visfatin and insulin resistance in obese female adolescents.
Kyu-Jin Lee, Yun-A. Shin, Kyoung-Young Lee, Tae-Won Jun and Wook Song
Marissa A. Kobayashi, Tae Kyoung Lee, Rafael O. Leite, Blanca Noriega Esquives, Guillermo Prado, Sarah E. Messiah and Sara M. St. George
Background: Previous literature has shown a negative relationship between parental stress and youth moderate to vigorous physical activity (MVPA). This study examined (1) the relationship between parental stress and adolescent MVPA, (2) the moderating role of family communication on this relationship, and (3) gender differences in these effects among overweight and obese Hispanic adolescents. Methods: Hispanic adolescents (N = 280, 52% female, 13.0 [0.8] y old, 44% obese, 12% severely obese) and their parents (88% female, 44.9 [6.5] y old) completed baseline measures for an efficacy trial. Adolescents self-reported MVPA in minutes per week for work, transportation, and recreation using a validated measure. Multiple regression analyses with interaction terms and multigroup methods were conducted. Results: There was a negative effect of parental stress on adolescent MVPA (β = −0.15, t = −2.018, P ≤ .05). This effect was moderated by family communication (β = 0.20, t = 2.471, P = .01), such that the association between parental stress and youth MVPA was stronger for adolescents with low levels of family communication. Furthermore, a multiple group model showed that the interaction was significant for boys (β = 0.27, t = 2.185, P = .03), but not for girls. Conclusions: Findings provide support that addressing parental stress and family communication may help facilitate MVPA among Hispanic boys, the most at-risk group for pediatric obesity.