The self-tracked life

The proliferation of personal digital devices that can record and transmit data has birthed a phenomenon. It's known as the "quantified self" or "self-tracking" movement, and proponents think it will motivate people to take charge of their health.

A self-tracker is anyone who keeps a daily record of personal health information-diet, exercise, mood, vital signs-often with the help of an electronic device. Various gadgets, like the Fitbit Tracker, the Basis watch, or the BodyMedia armband, are designed to measure temperature, record movements, detect sweat, monitor heart rate, calculate calories burned, or even track sleeping habits. The idea is that if people can see their own behavior and vitals charted over time, they can better identify positive or negative health patterns and make changes to stay in shape.

But will self-tracking devices motivate the unmotivated? One study presented at an American Heart Association meeting last month reported that overweight adults who received daily feedback on diet and exercise goals from an electronic device were slightly more likely to lose weight. But the study participants slacked off keeping their goals after several months. And a doctor writing on the Technology Review website last year said diabetes patients in one of his programs were often uninterested in regularly uploading their glucose readings to a database, even though a device made it simple for them to do so.

But the doctor said self-tracking did motivate him to do yard work: Wearing a BodyMedia armband, he learned he was burning more calories "pulling weeds, squatting, standing up, trimming branches, [and] hauling bushes" than by cycling on the weekends.

Self-tracking is becoming mainstream. The Nike+ FuelBand, an electronic wristband that debuted earlier this year, records subtle movements and deciphers whether the user is walking, running, playing basketball, playing tennis, or doing other common activities. Users upload their data to the Nike+ website, which charts their daily progress, keeps records of calories burned and miles covered, and allows them to share records on Facebook and challenge friends.

Nike+ is sparking motivation by prompting its members to set a daily exercise goal-then visually reminding them when they meet it or fall short. My brother, Evan, told me his FuelBand prods him to "get outside and shoot around on the hoop."

High-resolution history

Old map lovers, rejoice! A new online portal, Old Maps Online, provides free access to thousands of historical maps from around the world. Go to the website (oldmapsonline.org), double-click China, Africa, or anywhere else on the home page, and the screen will zoom in and offer viewings of high-resolution, antique maps featuring the location you've chosen.

For instance, you could view the Keith Johnston 1861 map of the Western United States, displaying rivers, mountain ranges, and political boundaries before Nebraska Territory had been divvied up to create parts of Wyoming, Montana, and other states. Or you could see the streets, parks, and boroughs of London as recorded in 1832. A world map from 1700 leaves half of North America and Australia blank, demarcating the geographical knowledge of the time.

The University of Texas also hosts a historical map database (lib.utexas.edu/maps/historical/index.html), though the site is less visual, with maps categorized by topic. -Daniel James Devine