Spark trackingIf you scour the internet for forums, discussion boards and customer reviews on pedometers, the top question and concern mentioned over and over again for those looking to buy a pedometer is regarding its accuracy.

Generally, the accuracy of an acceptable pedometer should have an error rate of 10% or less. However, many factors need to be considered, such as the type of pedometer, how it is worn, the make and model of the pedometer and user input.

What Types of Pedometers Are More Accurate?

The older types of pedometers are the spring-load models, using either a coiled spring mechanism or a hairspring mechanism:

  • The hairspring models are the least expensive type offering few features. They become less accurate as time passes due to the spring losing its elasticity with use.
  • The spring on the coil models has less probability of loosening so it has a longer life. The newer electronic versions offer additional features such as a clock, weekly activity log and number of calories burned and much more. The coil model is usually worn on a belt or waistband attached by a clip. The pedometer must stay in a vertical position to get an accurate reading.

The next type is the accelerometer (also known as piezoelectric) pedometer which is more expensive but also more accurate. They are also more durable with no moving parts that can wear out. They use 2- or 3-axis MEMS (microelectromechanical systems) technology, which accounts for more accuracy and variation in the placement of the pedometer as it measures inertia, unlike the spring-load types that rely on hip motion and must be clipped in a vertical position. The best of these pedometers have a ± 5% accuracy.

Last, we have the GPS (global positioning satellite) pedometer which can measure speed, distance, pace, time, laps and even show you your way back to your starting point. They are the most expensive type as they usually come with many features from stopwatch and alarm functions to providing data like heart and pulse rates, calories burned, steps per minute, to name a few. The only problem with GPS pedometers is satellite signal interruption by things such as tall buildings, wooded areas and weather that affect the accuracy.

What Affects A Pedometer’s Accuracy?

There are a lot of factors that can significantly affect a pedometer’s accuracy but the 2 most important factors are:

  1. Where you wear it –
    As mentioned earlier, the spring-load type pedometers must be clipped securely and vertically to a belt or waistband to get an accurate count. The more accurate pedometers with an accelerometer mechanism are less affected by positioning and are usually worn in a pocket but also clipped to a bra or shoe and, of course, the wristband models on the wrist.
    Having read many customers reviews and forum discussions, I found varying opinions about where to wear a pedometer to get the most accurate step counting. What works best for one user, fails for another. The best advice I can give is to experiment with different positions until you find what is most comfortable and what works best for you.
  2. Your stride length –
    Crucially important to a pedometer’s accuracy is to input your own correct stride length as it varies from person to person. Follow the instructions included with your pedometer carefully but if you still are not getting accurate counts, you can increase or decrease your stride length depending on whether your pedometer is undercounting or overcounting your steps respectively.Check out this simple way of measuring you stride length.

    Or you can also try averaging the results from the following suggestions:

  • Water Method –
    Pour water on concrete into a puddle and step in it until the bottom of your shoes are wet. Then walk out of the puddle at a normal gait for about 25 steps. Measure the distance from the heel of the left footprint to the heel of the right footprint in inches and divide by 12 inches. This will give your stride length in feet.
  • Short Distance Measure –
    Measure and mark a straight line of 10 to 20 feet. Walk at a normal gait beside the line and then divide the marked distance by your steps.
  • Long Distance Measure –
    If there is a measured track in your neighborhood, walk about a mile in a normal gait. Then divide the known distance by your steps.

Other Factors Affecting A Pedometer’s Accuracy

There are many other factors that cause some pedometers to overcount or undercount steps:

  • Slow walking gait – Spring-load pedometers have a harder time detecting steps taken at a slow pace (under 2.5 mph) because there is less hip movement.
  • Reset button is not recessed – Make sure your model has a recessed reset button otherwise you may accidentally press it and cancel your current session.
  • Non-ambulatory activities – Activities such as stationary cycling or rowing are harder to detect and count. Some pedometers require them to be logged into your online data where they don’t count for steps but for calories burned.
  • Walking uphill and downhill – When you walk uphill or downhill your stride length decreases and increases respectively and thus may account for incorrect step counting.
  • Old spring mechanism – Inaccurate step counting occurs as the hairspring and coil springs of the spring-load models wear out with use and age.
  • Distance and calories burned are generally the least accurate measurements

Consistency Over Everything

Unless you are a professional athlete or a fitness buff where minute details and stats matter enormously, it is not a good idea to obsess too much about the accuracy of your pedometer.

Even if your pedometer is off by a few steps, what really matters is the consistency of its results. If you walk the same measured route every day that you know is 1000 steps but your pedometer records 900 steps every day, don’t stress. What really counts (see what I did there!) is that you can still see the progress you’ve made and how more active and healthy you are becoming. Isn’t that what is really important?

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