Daily physical activity, human development index and insomnia in a representative sample of Brazilian adolescents: a cross-sectional analysis

Abstract

Insomnia is defined as persistent difficulty in falling asleep and staying asleep, despite adequate sleep opportunities, 1 and is considered to be the most common sleep disorder during adolescence, with an estimated prevalence ranging from 6% to 30% in this age group. 1 Previous research has shown that insomnia is associated with symptoms of depression, substance abuse, poor school performance, mood disorders, 2,3 social withdrawal and loneliness, 4 lower emotional regulation, 5,6 anxiety and suicidal thoughts. 7 Despite the recommendations that adolescents should sleep for 8 to 10 hours per day, 8 few young people achieve sufficient amounts of sleep, 9 which converges on a secular trend of reduced sleep duration among children and adolescents. 10 This scenario highlights insomnia as an important public health issue, as well as demonstrating the need to establish effective and suitable ways to address this problem during adolescence.In this regard, the scientific literature provides arguments for different strategies for treating insomnia, such as cognitive-behavioral therapy and pharmacotherapy. 11,12 However, although similar efficacy has been demonstrated between these therapies for treating insomnia, 13 both of them are difficult to apply on a large scale, especially in the context of developing countries. 14 Thus, studies have pointed towards physical activity (PA) as a possible low-cost strategy for reducing the effects of insomnia among adolescents. 15 In a meta-analysis on 12 studies that investigated the relationship between PA and sleep among adolescents, it was concluded that individuals with higher PA levels, assessed subjectively and objectively, were more likely to present better sleep quality. 16 Furthermore, the results from a clinical review demonstrated that moderate aerobic exercise training could be prescribed as pertinent non-pharmacological treatment for sleep