In late 2019, a virus outbreak led to a previously unknown disease called COVID-19, which subsequently spread worldwide. There are at present more than 200 countries and more than two million people infected (Chinazzi et al., 2020). The most common symptoms of this disease include: fever, dry cough and tiredness. Some infected people have only minor symptoms. Most of them (about 80%) recover from the disease without needing hospital care. About 1 in 5 people who get COVID-19 eventually develop a severe condition and experience breathing difficulties. Older people and those with previous health conditions are more likely to suffer from serious conditions. However, anyone can get COVID-19 and become seriously ill (Organización Mundial de la salud, 2020). In Spain, the pandemic brought about by the COVID-19 virus, forced the government to declare a state of alarm (Royal Decree 463/2020, of March 14), for the management of the health crisis situation (Moncloa, 2020).

Since the activation of the health emergency measures, the outbreak of COVID-19 in Spain began to be controlled in May with the start of the de-escalation stages (see Table 1, which shows the chronology of stages implemented in Castile and Leon, the Autonomous Community to which the region in the study belongs). Population efforts and health resources have been key in this control. Confinement measures included the closure of educational centers in the middle of the academic year without reopening them before the end of the school year, which led to various academic and personal difficulties. In the case of adolescents, this situation has brought about changes in both their psychosocial aspect and academic performance, as well as negatively affecting their mental health as a result of the COVID-19 virus (Liang et al., 2020). The school closures due to the pandemic have affected students (UNESCO Education, 2020). From 15 March to 17 May there were 65 days of confinement for this healthy population. In this context, this research is focused on the well-being of the adolescent population, and to seeks not only to determine whether there is a change, but also to find out how these variables behave: stress, emotional intelligence (EI) and the intention to use substances, in particular cannabis.

Previous studies have shown that, despite public awareness, confinement causes stress levels that affect quality of life during epidemics (Yuan et al., 2020). Recent research with adolescents (Yang et al., 2020), in Wuhan, shows that there is widespread psychological stress in this population, despite positive behavioral compliance with personal hygiene practices. The literature indicates that effective coping strategies can protect individuals from mental health problems when dealing with emergency situations (Xu and He, 2012). On a general level, the literature to date indicates differences between the sexes in terms of stress levels. Adolescent girls generally have more stressful life events, academic, family, social or friendship, personal, and total stress than teenage boys. However, it is adolescent girls who present higher values of perceived EI (Veytia López et al., 2019). Not only the female gender, but also the student status and physical symptoms are associated with a greater psychological impact of the outbreak, and higher levels of stress, anxiety and depression (Wang et al., 2020). Therefore, students who engage in vigorous physical activity report better mental health and less perceived stress than those who do not (Vankim and Nelson, 2013). In Spain, during to the confinement resulting from the COVID-19 virus, a negative association of previous and current physical activity with stress scores was found in the general population (Planchuelo-Gómez et al., 2020). Furthermore, it is also adolescent girls who perceive and understand emotions better, as well as perceiving greater amounts of stress at a later age (Schoeps et al., 2019). In this sense, EI and perceived self-efficacy seem to play a determining role in stress levels and their satisfactory management in academic contexts, with benefits in both their emotional level (Mascia et al., 2020) and academic performance (Navarro-Mateu et al., 2020). Thus, emotional regulation and general well-being are improved by leading a healthy lifestyle (Lubans et al., 2016). The practice of physical activity has been found to improve personal well-being and disease prevention (Ahn et al., 2016). Students who have a better understanding of their emotions demonstrate higher levels of physical activity (González-Valero et al., 2019). The literature highlights the relationship between physical activity and the different dimensions of EI. In studies focusing on the university population, those young people who were physically active in their free time showed higher levels of EI (Gutiérrez and Araya-Vargas, 2014), and particularly of repair and attention (Acebes-Sánchez et al., 2019). Those college students who exercised regularly and continued their exercise habits during the COVID-19 outbreak correlated significantly with lower scores on the depression, anxiety and stress scale (Deng et al., 2020). However, the confinement brought about by COVID-19 virus reduced the outdoor activities of adolescents, and it has been seen how, although boys are more resistant to social isolation, girls experience a greater impact on their moods (Zhang et al., 2020).

The current situation affects children, adolescents and families so exceptionally. As educational centers were closed, social contacts became greatly limited, and leisure time activities were canceled (Fegert et al., 2020). Measures implemented in the field of physical distancing resulting from the COVID-19 virus have been associated with a decrease in physical activity and well-being, an increase in loneliness and Internet use among adolescents (Munasinghe et al., 2020). Among the mental health problems related to quarantine, we find depression, mood swings, anger, insomnia and emotional exhaustion (Brooks et al., 2020). However, most of the studies published to date focus on the general population, with less research into adolescents. In the face of stressful events, high levels of acceptance and coping strategies, such as low self-blame, can help people to be better prepared to respond to stressful events and facilitate the use of active, problem-centered resolution (Finkelstein-Fox et al., 2019). Thus, adolescence is one of the highest risk stages for both the initiation of substance abuse and its continuance (del Carmen Pérez-Fuentes et al., 2018), during which cannabis use may appear as an escape mechanism from stress (Low et al., 2012).

Cannabis is the third most widespread drug among students aged 14–18 and the most prevalent illegal substance according to the most recent data from the ESTUDES survey (ESTUDES, 2018). Currently, in Spain, 3 out of 10 young people admit to having used cannabis, and the prevalence of those who have used it at some time in their lives is slightly higher in males (34.5%) than in females (31.5%) (ESTUDES, 2018). Cannabis users cope with stress less flexibly (Kruczek, 2017), and also show lower values of emotional repair (Sandín, 2003). The literature indicates how alcohol and tobacco use is related to EI, resilience and family functioning, the latter being both a protective and risk factor, depending on the circumstances (Molero Jurado et al., 2019). Similarly, while a higher level of emotional regulation capacity is related to a lower frequency of substance abuse, a higher level on the adaptability scale has been associated in a study by Kun et al. (2019) with more frequent substance abuse. Evidence from the literature reveals a negative association between cannabis use and adequate physical activity among adolescents in low- and middle-income countries. This study also shows how adolescents who have used cannabis in the past 30 days are less likely to achieve adequate levels of physical activity (Ashdown-Franks et al., 2019).

In order to provide evidence to promote mental health in adolescents, the aim of this study is to describe and analyze the relationships between the variables of stress, EI and intention to use cannabis in healthy adolescents, during and after the end of the confinement stage of the COVID-19 pandemic.