He Says Monitors Have as Many Bells and Whistles as You Need. And Maybe More.

"It is not a watch," said Garmin systems engineer Claudette Stevenson, who said battery time was one compromise the company made in favor of size: Previous Forerunners were about the size of a cellphone, worn on the wrist.

Comparable models, Polar's RS800 and Suunto's t6c (both about $400), have conventional, user-replaceable watch batteries, though keep in mind that their GPS units use a separate set of AAs.

How geeky can you get?

All three companies offer software and online tools to upload data, analyze them and plan workouts while you're sitting at your computer. On this front, Polar's RS800 series and Suunto's t6c have stronger analytical tools than Garmin.

Based on accumulated effort, Suunto rates each workout on a 1-to-5 "training effect scale," with a 2 being basic maintenance, a 3 meaning you're getting a bit stronger and a 5 meaning you overdid it. (One of its watches, the t4, uses that information to recommend workouts.)

John Lally, who manages the company's training products in North America, said the aim is to "be the best analytically for saying if you have improved your fitness" and to broaden the appeal of those tools to more than serious runners and bikers.

Polar converts a run workout into a "running index," related to your oxygen consumption.

All three companies allow you to set up custom workouts including a warm-up time, a speed goal and a set of intervals. Polar has an online database of downloadable workouts (currently just a few but with plans to expand). Garmin offers a virtual partner, a little icon running buddy to pace yourself against, which is a bit more interesting than the beep you'll get from Polar or Suunto if you fall below the target pace.

How connected do you like to be?

Garmin has nailed this category. Its uses a Bluetooth-like technology called ANT to automatically upload data from its watches with nary a button push. It just happens when you return from a workout, as soon as you get in range of your computer. The same technology allows you to trade workouts with a friend. Suunto's higher-end t6c comes with a USB cord that clips onto the watch -- an almost automatic download that is also convenient. Polar's RS800 uses an infrared-USB link that requires a few clicks to get rolling but seems to work fine. Be sure that you know what you are getting: Some of the models require you to buy a separate piece of gear to do the downloading.