2010年7月15日星期四

The Nike Lance 4 Titanium Cycling Watch

Features of the Nike Lance 4 Titanium Cycling WatchAltimeter with Zero Drift Technology. The Lance 4 uses a special algorithm toattempt to distinguish between barometric pressure changes, and actual altitudechanges. Measure your ascent/decent rate, current altitude, and the maximumaltitude achieved.Barometer. (The watch even charts changes in barometric pressure.)Real-time digital compass. Displays your current heading as well as both magneticor geographic north (see my reviewof the Tissot T-Touch for an explanationof the difference).
The Nike Lance 4 Titanium Cycling watch is the star of Nike's ACG Oregon outdoorwatch collection. Inspired and partially designed by five-time (consecutive) Tourde France winner Lance Armstrong, the Nike Lance 4 packs an impressive setof features into a relatively lightweight and even fairly nice looking (in an outdoorsports watch kind of way) titanium case.Before I list all the features of the Nike Lance 4, I want to talk about one featurein particular: the altimeter. Since cycling -- and especially the Tour de France-- is so much about ascents and elevation, naturally the Lance 4 contains an altimeter.The problem with most altimeters which are built into watches, however, is thatthey are barometric altimeters, which means they attempt to measure your altitudeby measuring the atmospheric pressure, and in some cases, the temperature.That also means natural changes in atmospheric pressure dramatically influencealtitude measurement. Usually the best way to use a barometric altimeter is tocalibrate it before you begin your ascent using a GPS, map, or a nearby sign, thento measure your ascent as quickly as you can before the atmospheric pressure changes.Since that obviously won't work for races that span days or weeks and hundredsor thousands of miles, Nike incorporated their patented Zero Drift technology intothe Lance 4 cycling watch. Zero Drift technology is apparently able to determinewhether a change in atmospheric pressure was caused by changing weather patterns,or by an actual change in altitude. Very clever, assuming it works.