Developmental Trends in Sexual Attraction Among Puerto Rican Early Adolescents in Two Contexts

Sexual attraction (SA), the earliest stage of sexual orientation, is scarcely studied. This prospective study examined, over 3 years, prevalence, changes in SA, and the role of context, among 946 Puerto Rican youth, aged 11–13 years at initial assessment in the South Bronx (SBx), New York City, and Puerto Rico (PR). Overall, 98.1% of boys and 95.3% of girls reported opposite-sex only SA at some point, whereas 13.8% of girls and 12.0% of boys reported any-same SA. Opposite-sex only SA increased over time, whereas other SAs decreased except for any same-sex SA among SBx girls. Girls in the SBx and younger youth in PR reported more any same-sex SA. Context and culture may play a role in the developmental trajectories of adolescents’ SA.     

Activity of periscapular muscles and its correlation with external oblique during push-up: Does scapular dyskinesis change the electromyographic response?

Scapular dyskinesis is the term used to describe changes in the positioning or movement of the scapula. Such dysfunction is associated with changes in the activation of the scapular muscles. However, the influence of the axial muscles on the scapular muscles activity of subjects with scapular dyskinesis is unknown. This study aimed to compare the electromyography (EMG) activity of periscapular muscles and its correlation with the external oblique muscle during the execution of push-up performed in different surfaces, in volunteers with and without scapular dyskinesis. Thirty-six men, divided in two groups (control and dyskinesis), performed push-up on stable and unstable surface. The EMG activity of serratus anterior (SA_5th and SA_7th fibers), upper (UT) and lower (LT) trapezius, external oblique (EO) was recorded during execution of each task condition. Statistical analyzes were performed using two way ANOVA repeated measures and Pearson correlation. It was observed effect of interaction between factors, being evidenced increased activity of UT, SA_7th and OE for the control group and decreased activity of SA_5th, SA_7th and EO for dyskinesis group during execution of push-up on unstable surface. In both groups positive correlations (r > 0.47) were observed between EMG activity of SA and EO. In the exercises tested, there seems to be an anatomical and functional relationship between the SA and EO muscles. The use of the unstable surface promotes increased neuromuscular demand, but the neuromuscular strategies appear to differ between groups.