Physical Activity, Inactivity, and Health During Youth-The Year That Was 2017.

It is well known that physical activity is important for children's current and future mental and physical health. Despite this, there appears to be a secular decline in children's physical activity (Cameron et al. [ 2 ]; Dalene et al. [ 3 ]). Furthermore, (frustratingly) interventions aiming to increase children's physical activity have limited success (Metcalf et al. [ 10 ]), demonstrating a need for more information on the amenability of activity levels to change.