The new Guidelines on Physical Activity and Sedentary Behaviour published by the World Health Organization are notable for what is missing: the minimum time for an exercise session. Similar to previous guidelines, these recognize the importance of regular activity on physical and mental well-being. The guidelines recommend a target of 150 to 300 minutes per week of moderate activity (such as brisk walking) or 75 to 150 minutes per week of vigorous activity (such as running) or a combination of the two. Gone is the requirement that your exercise minutes need to be conducted in chunks of at least 10 minutes. My research group investigates the role of regular physical activity on health and disease. Our research indicates the health and fitness benefits from exercise begin from the very first step of movement. These benefits continue to accumulate in a linear fashion up until 300 to 400 minutes per week of moderate activity. …