TY - JOUR T1 - Short and sporadic bouts in the 2018 US physical activity guidelines: is high-intensity incidental physical activity the new HIIT? JF - British Journal of Sports Medicine JO - Br J Sports Med SP - 1137 LP - 1139 DO - 10.1136/bjsports-2018-100397 VL - 53 IS - 18 AU - Emmanuel Stamatakis AU - Nathan A Johnson AU - Lauren Powell AU - Mark Hamer AU - Vegar Rangul AU - Andreas Holtermann Y1 - 2019/09/01 UR - http://bjsm.bmj.com/content/53/18/1137.abstract N2 - Starting and sticking to an exercise programme is challenging for most who are at risk of developing lifestyle-related chronic disease: the most physically inactive, unfit, and overweight or obese middle-aged individuals, that is, the majority of the adult population. The 2018 US Physical Activity Guidelines for Americans1 introduced a number of new elements that will undoubtedly change how we think about and promote physical activity (PA). Not to anyone’s surprise, the new guidelines abandoned the unsupported by empirical evidence idea that PA needs to be accumulated in at least 10 min continuous bouts to be health enhancing.1 This opens new exciting opportunities to capitalise on sporadic, incidental in nature, PA to improve the population’s health.Incidental PA is any activity that is part of one’s daily living that is not done with the purpose of recreation or health and requires no sacrifice of discretionary time. For example, walking or cycling to move from place to place, stair climbing and active daily chores, such as carrying heavy shopping1 and house cleaning. Inherently, incidental PA does not encounter the myriad of barriers to structured exercises, such as lack of time, costs, equipment, lack of skills or poor fitness. In itself, such a feasibility advantage may signal a turning point as fewer barriers mean that many more people can be incidentally active than recreationally active. What is far less clear is how to maximise the health impact of incidental PA and how to convince and empower people to be physically active in their daily lives. In this editorial, we address the first of these questions.The length of each incidental PA bout can vary from a ‘short and sweet’ few seconds, such as climbing a few flights of stairs 3–4 … ER -