You may not have heard of them, but they are increasingly everywhere. Accelerometers are making their way into all kinds of consumer electronics and are becoming a popular device for measuring a persons activity levels. In technical terms, an accelerometer measures an objects acceleration relative to free fall. Unlike a regular pedometer, which can only detect the motion of ones hips, the accelerometer can measure movement in three dimensions, in addition to orientation and vibration.
A number of devices, you are probably familiar with, contain accelerometers. For example, Apple's iPhone uses an accelerometer to determine how the phone is being held. The Nintendo Wii uses the technology in its hand held controllers. A few companies have come out with pedometer like devices that enable the wearer of the device to measure their daily activity levels. One startup company, FitBit (www.fitbit.com), has designed a very small device that can be worn like a paper clip and then wirelessly transmits measurements about the wearer’s activity and the quality of sleep to a website. The wearer can use the website to track their activity levels and get an overall picture on their energy expenditure. Other devices offer similar web based interfaces, however they require that you wear the device on your shoes. These types of devices will measure movement of your feet but will probably not pick up much activity for movement such as weightlifting, etc.
Wearing one of these devices can give you a good picture of how much energy you expend in a day. It has been shown that having access to this data can be a great motivating tool for increasing exercise and activity levels. If you can measure how small incremental changes in your daily routine can add to real numbers, you are more likely to continue with those changes.
Many people with a typical sedentary lifestyle are shocked to learn how little activity they get throughout the day after it has been measured by an accelerometer. Having access to data that can show you that you only had 15 minutes of activity or have only taken 500 steps today, is sometimes the kick you need to go for that evening jog or bike ride. So if you are looking for device that can help you reach your fitness goals, definitely look into some of the cool accelerometers out there.