New principles, the benefits, and practices for fostering a physically active lifestyle

The modern environment has led to an increased risk and incidence of sedentary lifestyles. When physical activity (PA) becomes insufficient, pathophysiological pathways are invoked and the future risk for chronic diseases and premature mortality increases. As a consequence, since the 1970s governmental agencies and medical societies have published guidelines to promote PA. The 2018 Guidelines for Physical Activity for Americans contain important updated guidelines, but many of these guidelines are not yet sufficiently known by the public or health providers. In addition, to make use of these guidelines, they need to be integrated with optimal behavioral interventions. Accordingly, this narrative review critically assesses five tenets that stem from the 2018 Guidelines and illustrates how these tenets can be integrated with tools and techniques for motivating individuals to initiate and maintain a more physically active lifestyle. The first tenet indicates that there is no lower threshold of PA that must be obtained before health benefits begin to accrue. Second, it is no longer required that PA be obtained in bouts of 10 min or more to "count". Bouts of lesser duration also count. Pending further study, new accelerometry data suggest that vigorous intermittent PA of just 1-2 min may also benefit health, such as that acquired by stair climbing or carrying heavy groceries. This has led to a new concept of promoting "lifestyle physical activity". Third, excessive sitting is health damaging if it is not accompanied by sufficient daily life PA or if it accrues over long uninterrupted bouts. Fourth, it is essential to incorporate resistance exercises for optimal health and to promote successful aging. Fifth, a wealth of new evidence indicates that PA strongly protects and promotes all aspects of brain health and may improve cognition even after a single bout of exercise.