A GPS watch can help you get the most out of your training and fitness time, and keep you on pace during a race. GPS watches are more accurate than devices that measure your strides, and don't require any supplemental wires or in-shoe sensors. You can use a GPS watch on a bike, during a run or hike, or for just about any outdoor activity. Most GPS watches are water-resistant and durable. They may also be linked to computer software and websites that enable you to upload and analyze data, providing in-depth but easy-to-update and access training logs. Read and submit GPS watch user reviews.
One of Garmin's newest GPS sports watches is also its lowest-cost model, the Forerunner 110. It may be the right GPS watch for you, if you don't need high-end extras, such as complete waterproofness (although the 110 is rated water-resistant). The Forerunner 110 gives you the key "how far and how fast" facts, but not pacing alerts, time/distance alerts, or an altimeter, for example. The 110 GPS watch does however work great with a heart rate monitor, and it calculates calorie burn taking into account heart rate (in addition to body weight), just like the higher-end Garmin models. You may also upload workouts from the 110 to Garmin's free online Connect services for the same great training log and analysis features other Garmin users enjoy.
Stepping up from the Garmin Forerunner 110 to the 210 model gives you indoor training capability. The Forerunner 210 is available with a stride-sensing foot-pod that attaches to your shoelaces, and feeds real-time distance data to the watch. This makes it fully functional during indoor treadmill training, very important to some athletes. Like the 110, you may also pair up the 210 with a heart rate monitor strap. The 210 also has interval training settings and features, while the 110 does not. The two watches are otherwise virtually the same. I've enjoyed running with the 210, and it's so compact, I find myself wearing it as a casual wristwatch as well.
Those who need a truly waterproof GPS sports watch with a load of features (sound like you, triathletes?) need to check out the Garmin Forerunner 310XT. The 310XT is a bit bulky compared to its 405-model cousins (also reviewed here), but it's all business. The 310XT has full-featured run, swim, and bike modes and its battery lasts 20 hours in full GPS mode, another important stat for triathletes. In my full review (see link below) I called it the most powerful and feature-filled GPS watch on the market, and that still holds true. The 310XT has an optional heart rate monitor strap, and is compatible with ANT+ devices, such as power meters. Upload workouts and races to the free Garmin Connect online service.
True GPS is still a relatively rare feature in sports watches (look out for watches that list GPS as a spec, but don't really have it), and Timex has just one model with true built-in GPS, the Global Trainer. The Global Trainer GPS watch is designed for multi-sport athletes, and also carries the Timex Ironman Triathlon brand. Features include five customizable displays with up to four data windows each, 20-workout memory, pacer features, upload link to Training Peaks, and an optional heart rate monitor. It's also compatible with ANT+ power and other sensors. The Global Trainer has a rechargeable lithium-ion battery that lasts up to 15 hours in full GPS mode. Read the full road test and review.
The Forerunner 405CX is very similar to Garmin's lower-cost 405, also reviewed here, except that it comes with a heart rate monitor strap included, and uses heart rate monitor data to help calculate a more accurate calorie burn statistics. The 405CX GPS watch has many features for the advanced athlete including measuring time, distance, pace, heart rate, calorie burn, and easy uploads to the Garmin Connect website. Like the 405, the 405CX has a sleek appearance that doesn't look out of place for casual and sports use. Other key features of this GPS watch include customized goals, pace and heart rate range alerts, customizable displays, and "courses" (compete against previous activities).
The Forerunner 405 is very similar to Garmin's higher-cost 405CX, also reviewed here, except that it does not come with a heart rate monitor strap, and does not include heart rate in its calorie-burn calculation (which is more accurate). However, the 405 is a highly competent and full-featured GPS watch for the serious athlete. The 405 has a 1-inch display that is easily readable in full sun, and like the 405CX, is controlled by a pair of buttons, and a touch-bevel. The 405 and 405CX are rated as water-resistant, but not waterproof. For a fully waterproof GPS watch, check out the Garmin 310XT in this review. Additional 405 features include time, distance, pace, heart rate, calorie burn, and uploads to Garmin Connect.
Polar offers two watch models with true, built-in GPS: The RS800CX, billed as a running and multisport GPS watch (shown here), and the nearly identical RS800CX Pro Team, geared more for cyclists. Some other Polar sports watches can be paired with a separate and costly G3 GPS sensor. Polar is known for the precision of its heart rate monitors, deep feature sets, and steep user learning curves, and that reputation holds true in the RS800CX. The RS800CX has altitude and barometer features; a plethora of heart rate and pace features, multiple bike settings, route mapping, and included ProTrainer 5 software. See full review link below.
Taking a different tack - more towards rugged outdoor use rather than strictly for sports like the other watches in this review, Suunto offers two similar GPS watch models, the X10, and X10 Military versions. Suunto's heritage is precise navigation, and that comes through in the X10s, which have seven compass features (such as heading in degrees and automatic calibration), accurate GPS, a barometric-assisted altimeter, and eight weather features, such as temperature, weather alarm, and weather memory. The X10 records routes, marks waypoints, and tracks speed and distance. Tracks may be easily imported into Google Earth. Overall, the X10 is a lightweight and rugged (rated water-resistant to 100 meters) tool.