A few GPS watches offer more advanced measurements. These include:
Cadence: Some watches measure cadence, or the number of steps per minute you take while running. This is done using a motion sensor in the watch, a chest-mounted monitor, or a foot pod. Although you may have heard that all runners should strive for 180 steps per minute, most experts now agree that there’s no universally desirable cadence. Even among individual runners, cadence can vary depending as you move from easy jogging to race pace. This article gives some guidance on making sense of cadence data.
Stride Length: Stride length is inversely proportional to cadence—the higher your cadence, the shorter your stride length at a constant speed. A shorter stride can help prevent overstriding, which is believed to lead to injury.
Vertical Oscillation: A few of the most advanced watches will measure the vertical motion of your torso—otherwise known as “bounce.” The idea is that the less bounce, the less extraneous work is being done, and the more efficient the runner is being, so a goal would be to have as little oscillation as possible.
VO2 Max: This is a measurement of the maximum amount of oxygen your body is able to consume, in milliliters per minute. The more oxygen one is able to consume, the more is available for muscles, and the harder a runner is able to work, which is why many runners want to improve their VO2 max rates.
Ground Contact Time: This is a measurement of how long, in milliseconds, your foot maintains contact with the ground, and is connected to a running style that includes faster cadence and shorter stride length. In general, runners have ground contact times of 160-300 milliseconds. Elite runners have shorter ground contact times—200 milliseconds or less.
Navigation: While many GPS watches record where you have been, a few include navigation-style maps to tell runners where they are, or how to get back to where they started. These are mostly available on watches marketed to trail runners, such as the Fenix line of watches from Garmin and Ambit series from Suunto.