Abstract
A new physical activity and exercise guideline (Exercise Guide 2006) asks Japanese, aged 20-69, to follow the slogan “Let's target 23 Ex (METs hour) per week by physical activity, of which 4 Ex by active exercise!” for preventing life-style related diseases. This amount of physical activity and exercise was conferred by systematic review on mainly epidemiological studies. Furthermore, this guideline shows level of physical fitness, especially maximal oxygen uptake necessary for preventing life-style related diseases.