A pedometer can be an excellent motivational tool for exercise inspiring you to keep to your fitness regime. The pedometer measures our body motion, counts our footsteps and converts this in to a distance by knowing the length of your usual stride.
When running or walking it can be difficult to calculate distances so a pedometer will help motivate you and enable you to record training distances. Some people choose to waer a pedometer all day and this can help you work towards your goal. The recommended number of steps is 6000 for health, 10,000 for weight loss. For weight loss, an uninterrupted walk each day of 4000-6000 steps is recommended.
If you are after complete accuraccy Timex has recently introduced a speedometer that tracks your speed and distance continuously using GPS.