Regular sports practice offers many benefits to health at any stage of human development and, particularly in adolescence, determines the gain from enduring habits of practice until adulthood (Lopes, Maia, Oliveira, Seabra, & Garganta, 2003; Perkins, Jacobs, Barber, & Eccles, 2004; Scheerder et al., 2006). Among these benefits, we can find prevention and control of risk behaviour such as consumption of tobacco and alcohol; and its contribution to healthy growth not only physical but also psychological (Cavill, Kahlmeier, & Racioppi, 2006). The main objectives of this study were: i) review, by gender and age, the level of sport, the consumption of tobacco and alcohol and the satisfaction with life of students of the third cycle of basic education who attend schools of Continental Portugal; ii) check the relationship between sport and other variables described in this population. The instruments used were the "Inventory of Health-related Behaviors of Adolescents" (Corte-Real, Balaguer, & Fonseca, 2004) and "Scale of Satisfaction with Life", translated and adapted version of the Satisfaction with Life Scale-SWLS (Diener, Emmons, Larsen, & Griffin, 1985). The sample consisted of 5,624 adolescents (53% female and 47% male) aged between 12 and 17 years ((X) over bar = 14.33; sigma = 1.359). The main results drawn were as follows: i) low levels of regular sports practice, especially in women, with a tendency to decrease with age; ii) consumption of tobacco significantly similar between genders, increasing with age; iii) significant alcohol consumption, especially in males, increasing with age; iv) consumption of tobacco very similar in the three levels of sports practice; v) high consumption of alcohol in young people with higher sports practice; vi) young people with higher sports practice had a higher degree of satisfaction with life. These results point clearly to the urgent need for measures at home and school, to support young people in the choice of a healthier lifestyle, including the acquisition of a more active lifestyle. The results also suggest that the full potential of sport, to promote behaviour which protects health and healthy lifestyles, might not always be used, so it is crucial for all physical education professionals and coaches to use, continuously and correctly, this "tool", the sports practice, to promote healthy habits and lifestyles.