Physical inactivity is an important public health problem all over the world and one of the leading risk factors for noncommunicable diseases mortality. Sedentary lifestyle is responsible for the premature death of 5.3 million people worldwide. Obesity is an endemic affecting nearly one-third of the adult population in Hungary and combining it with overweight people, means half of the population. In Europe, one in three children is obese. Unhealthy lifestyle is a risk factor for numerous noncommunicable chronic diseases, negatively affecting both physical and mental health, limiting the quality of life, and reducing life expectancy. Lifestyle medicine, particularly regular physical activity, plays a very important role as a low-intensity intervention. Regular physical activity is a widely accessible and effective tool for both prevention and therapy, significantly contributing to the improvement and long-term maintenance of physical and mental health. It also enhances the quality of life and increases life expectancy. Numerous physical and mental diseases remain undiagnosed and therefore untreated. This fact makes exercise particularly important for disease prevention at all stages of life. Despite the long-recognized benefits of regular physical activity, it is seldom mentioned in medical literature and, with few exceptions, it is almost absent from treatment protocols as a targeted therapeutic intervention. The scope of the summary is to introduce how regular physical activity, as one of the pillars of lifestyle medicine, and targeted exercise programs can be used in primary, secondary, and tertiary prevention as low-intensity interventions.