The Nike + iPod Sport Kit combines shoes, sensor, receiver, and iPod Nano to create a pedometer system designed to give runners and walkers feedback on their workout. The receiver plugs into the bottom of a Nano; the sensor slips into a pocket under the insole of specially designed Nike+ sneakers.

The system tracks speed, time, distance, and calories burned as you walk or run, displays the data on the Nano, reports it through your earphones, and can upload it to the NikePlus.com Web site. The site saves information from every workout and lets you set goals or challenge other members of the Nike+ community. We paid $29 for the sport kit itself, $149 for a 1GB iPod Nano, $29 for a Nike Sport armband, and $100 for Nike+ sneakers (the least expensive are $85). Grand total: $307.

How we tested. Two staff members used the kit as they ran on a mile-long loop of pavement. They tried the sensor in a Nike+ shoe and placed in a shoe wallet attached to the laces of another brand of footwear.

What we found. When the testers moved at an even pace, the kit was extremely accurate, especially when we had it calibrated for their individual strides by having them cover a specific distance. But if you mix jogging and sprinting, the system can be less than 90 percent accurate for pace and distance. For someone running a mile in 6 minutes 30 seconds, the readout might say 7 minutes. The system was no more or less accurate with the special Nike+ shoes.

CR’s take. The Nike + iPod Sport Kit is worth considering if you tend to run at an even pace and can use some motivation. Buying all the parts is expensive, but if you already have a Nano and sneakers, you can get away with spending about $40 for the kit plus a shoe wallet that will hold the sensor and attach to a sneaker lace. If you buy an armband for the Nano, be sure it lets you view the screen (ours didn’t).