Is My Pedometer Accurate?
A pedometer, by definition, is a device to measure the number of steps taken. Pedometers are nowadays much more elaborate than just counting steps, but their core measurement is how many steps you take.
Inside modern electronic pedometers is a small accelerometer, which detects movements in many directions such as the hips moving side to side or up and down with each step, or the arm swinging backwards and forwards. The device has been fine-tuned to work out which of these movements represents a step.
There are literally hundreds of pedometers on the market, with a wide range of costs and an equally wide range in quality. Even phones now have built-in accelerometers so they can also be used as a pedometer. With the large range of available devices comes a wide range of accuracy.
It is important to know if the steps are accurately being counted, especially if you are working out the distance traveled or energy expenditure. A simple way to calibrate the device, that is to determine if it is accurately counting all the steps, is by walking and counting. Simply walk for some time and manually count the number of steps you take, and compare this to the number that is displayed on the pedometer. The longer the distance and the number of steps, the better your accuracy check. You should also then jog and run the same number of steps and see how this compares.
Is it really steps it is measuring, and what about other movements? Depending on the device, it may pick up other movements and count them as steps. This is not always a bad thing, as the pedometer can then be used to crudely measure your daily activity. With some activities, you do not always take 'steps', for example, if the pedometer is on your wrist it may pick up 'steps' when you are vacuuming, or miss 'steps' if you are cycling.
Another test of the accuracy of your pedometer is to compare devices to each other. If you have more than one pedometer, put them on your wrist at the same time, and even put your phone in your pocket. Then do the walk and count test as previously described. Theoretically, all the devices should measure the same number of steps for a given walk or run, but you will find that no two devices give you the same measurement.
Many pedometers also calculate the distance traveled, which requires knowing your stride length, something it cannot measure itself. You need to input that information, luckily it is something that can be determined quite easily. Then it is simply the process of multiplying your step count by the average step length to get the total distance traveled. Be aware that your stride length can vary considerably. For example, your stride length will be longer when you are running than it is when you are walking. Also, your stride is likely to be shorter when going uphill as opposed to walking on a level surface. Any error in the stride length will just be multiplied if your pedometer is not measuring the step count accurately.
- See the Pedometer home
- Calibrating Stride Length — determine your average step distance for use with your pedometer.
- Fit-bit — a review of the pedometer with extras
- Energy Expenditure using a Pedometer — by counting steps you can estimate how much energy you are using.
- If you haven't got one yet, visit the Pedometer Store for a selection of pedometers to purchase.
- Calibrating fitness testing equipment