The Nike+iPod Sports Kit is a device which measures and records the distance and pace of a run. It was jointly developed by Apple Computer (which develops the iPod line of MP3 players) and the Nike shoe company.
The Nike+iPod consists of a small accelerometer attached to or embedded in a shoe, which communicates with either the Nike+ Sportband or a receiver plugged into an iPod nano or an iPod Touch 2nd Generation. If using the iPod, iTunes software can be used to view the walk or run history.
The sensor and iPod kit was announced on May 23, 2006 but for a short time was unavailable for purchase. The kit is able to store information such as the elapsed time of the workout, the distance traveled, pace, or calories burned by the individual wearing the shoes, and display it on the screen or broadcast it through the headphones of an iPod.
The sensor and Sportband kit was announced in April 2008. The kit allows users to store run information without the iPod Nano. The Sportband consists of two parts; a rubber holding strap which is worn around the wrist, and the receiver which resembles a USB key-disk. The receiver displays information comparable to that of the iPod kit on the built-in display. After a run, the receiver can be plugged straight into a USB port and the software will upload the run information automatically to the Nike+ website.
In August 2008, Nike lauched its Nike+ iPod Gym which expands its technology to include workouts on exercise equipment including Life Fitness Treadmills, Cross-Trainers and Upright and Recumbent bikes. Users don't need a Sports Kit to record these workouts; instead, they simply plug their iPod nano into the iPod connector on the cardio equipment in their gym. The Nike+ website lets a user track this data as "cardio miles," based on the work equivalent of running that number of miles.
On September 9, 2008, Apple Inc. announced its the 2nd generation iPod Touch with built-in Nike+ capabilities, which eliminates the need for an external receiver to be connected.
Sports kit equipment
The kit consists of two pieces: a piezoelectric accelerometer with a transmitter that is mounted under the inner sole of the shoe and a receiver that connects to the iPod. Nike recommends that the shoe be a Nike+ model with a special pocket in which to place the device. Nike has released the accelerometer for individual sale meaning that consumers no longer have to purchase the whole set. However, other vendors sell pockets which hold the accelerometer and tie to shoes from any manufacturer. No matter how the accelerometer is integrated with the user's shoes, care must be taken that it is firmly fixed in place and will not jerk around while in use, which would degrade the accuracy of the accelerometer.
Sports kit usage
The Sports Kit can be used to track running, which it refers to as "workouts". New workouts are started by plugging the receiving unit into the iPod, then navigating through the iPod menu system. The user chooses a goal for the workout, which might be to cover a specific distance, or burn a number of calories, or workout for a specified time. A workout can also be started without a goal, which is called a "Basic Workout". When the workout goal has been set, the receiver seeks the accelerometer, possibly asking the user to "walk around to activate [the] sensor". The user then must press the center button on the iPod to begin the workout.
Audio feedback is provided in a the user's choice of generic male or female voice by the iPod over the course of the workout, depending on the type of workout chosen. For goal-oriented workouts, the feedback will correspond to significant milestones toward the goal. In a distance workout, for example, the audio feedback will inform the user as each mile or kilometer has been completed, as well as the half-way point of the workout, and a countdown of four 100-meter increments at the end of the workout.
The iPod's control wheel functions change slightly during a workout. The Pause button now not only pauses the music but also the workout. Similarly, the Menu button is used to access the controls to end the workout. The Forward and Back buttons are unchanged, performing audio track skip and reverse functions. The Center button has two functions: audio feedback about the current distance, time, and pace are provided when the button is tapped once, while if the button is held down the iPod skips to the "Power Song" - an audio track chosen by the user, generally intended for motivation.
In addition to the in-workout audio feedback, there are pre-recorded congratulations provided by Lance Armstrong, Tiger Woods, Joan Benoit Samuelson, and Paula Radcliffe whenever a user achieves a personal best (such as fastest mile, fastest 5K, fastest 10K, longest run yet) or reaches certain long-term cumulative milestones (such as 250 miles, 500 kilometers). This "celebrity feedback" is heard after the usual end-of-run statistics.
While the Sports Kit can be used immediately after purchase, it will report more accurate results if it is calibrated before the first usage and then regularly afterwards. For calibration, the user finds a fixed known distance of at least 0.25 mile or 400 meters and then sets the Nike+ to calibration mode for the walk or run over that distance at the athlete's normal training pace. When the walk or run is complete, the device calibrates itself and future workout reporting will reflect statistics closer to that individual user's workout style. Consumer Reports magazine tested the device and found it accurate as long as you keep an even pace. In workouts with varied pace, accuracy was sometimes less than 90%. As walking and running strides can vary significantly, the device should be calibrated for each. In this regard, the Nike+IPod is inherently less accurate than a GPS monitor, which uses satellite technology to measure the actual distance covered in each workout.
In addition to tracking personal workout statistics, the Nike+ integrates directly with the Nike website. Workout data can be automatically uploaded to the website during an iPod sync with iTunes or through another program via the website's public API. The uploaded information is mostly not personally-identifying, but does also contain some personal statistics such as weight (if configured). Workout data is stored in XML files on the iPod, which has led some web and applications programmers to offer alternatives to the official Nike reports.
On October 19, 2006, new features were added to the Nike+ website, including the ability to name runs. Forums were also added, allowing users to meet and challenge other runners, ask questions, and give feedback. Recently, there have been several more additions to the Nike+ website including but not limited to: a challenge gallery where all user created challenges are viewable, the ability to name the route taken when running or walking, compatibility with the new iPod nano (fourth generation), a distance club to view everyone's total distance traveled, fastest 5K et cetera.
The sensor is an active device that continuously broadcasts without encryption a unique identifier when the user is walking or running, even when the user's iPod is not nearby. Privacy advocates claim that a malicious individual could exploit this fact for tracking or stalking purposes. With some fairly inexpensive tools, a stalker or thief could build surveillance devices to track a specific person or group of people, gather information about their daily schedules, and collect that information in real time or offline.
- Nike+iPod - official site at Apple's website
- Nike+ - official site at Nike's website
- Nike+iPod raises RFID privacy concerns - CNET News
- Running Tracker - an open source tool to analyze and to compare Nike+ workouts
- Neki++ - an open source workout management and visualization tool
- Life Fitness - gym equipment that works with Nike+
- Twiike - free service that automatically posts new Nike+ runs to the runner's Twitter account on sync