People who faithfully adhere to 10,000 daily steps may be surprised to learn that this widely accepted target did not originate as the result of years of scientific research.

Instead, it grew out of the marketing campaign for a Japanese pedometer invented in 1965. The name of the pedometer was Manpo-kei (10,000-step meter), and the ads said, “Let’s walk 10,000 steps a day!” More than 50 years later, that idea has retained its power.

Many researchers have studied the 10,000-step number to see whether it holds weight. The answer is yes, and no. Although 10,000 steps is not universally appropriate for all ages, genders and levels of physical function, it is considered “a reasonable target for healthy adults,” said a 2011 research review published in the International Journal of Behavioral Nutrition and Physical Activity.

Here’s why: Most Americans take 4,000 to 6,000 steps through general daily action — working, shopping, walking through parking lots, etc. If you add the 30 minutes of recommended exercise, that’s another 3,000 to 4,000 steps, and gets you close to the 10,000-step goal. It’s basic math. Keeping track of steps can prompt people to do more physical activity using manageable goals.

Someone who is less active may set a lower step goal. An increase to 8,000 steps will help an adult who was previously taking only 6,000 (fewer than 5,000 steps a day is considered sedentary). On the other hand, someone who already walks 10,000 steps may aim for 15,000. The idea is to be more aware of your activity level, and increase it as needed.