In 2005, the INPES Health Barometer survey collected data on the health-related behaviors, knowledge, and opinions of the French population. Using this information, the sports-related behaviors of 12- to 25-year-olds were cross-referenced with various health indicators. The objective was to compare the behavior of residents of the Île-de-France region with that of the rest of the French population and to measure changes in their sports participation since 1997. To ensure a sufficiently large sample for the Île-de-France region, an oversample of 12- to 25-year-olds from the region was created. Risk factors associated with engaging in sports were determined using logistic and linear regressions. The survey included 5,980 individuals. The study shows that sports participation is widespread among young people. No change has been observed since 1997, whereas time spent on sedentary activities has increased. Physical activity is synonymous with good health: athletes are less prone to depression and enjoy better physical, mental, and social health. However, physical activity may also be associated with a higher frequency of regular alcohol consumption (among young people over 18), as well as certain risk behaviors (more accidents in daily life and aggressive behavior). Although certain risky behaviors are associated with participating in sports, physical activity remains a protective factor for our health. (R.A.)