I started using both a GPS watch and the online platform Strava to track my workouts in 2014, thanks to receiving the Garmin Forerunner 620 as a holiday gift from my mom and my wife. I’ve tracked almost every run since then -- 1,984 runs to be precise -- and stand by the motto “if it’s not on Strava, it didn’t happen!” It’s hard to think of what running was like before my Garmin, even though I spent more than 15 years running races either without a watch or with a classic Timex sports watch.
These days, a Global Positioning System (GPS) watch like a Garmin saves me time from manually calculating basic metrics, like distance and speed, as well as more advanced ones like heart rate and cadence. While my Garmin keeps me accountable and has likely helped me become a faster runner, it can also cause anxiety and stress. Runners can become overly dependent on their GPS watches, forgetting how to run by "feel" and listen to their bodies, which is critical to becoming a better runner. How and when should you decide if a GPS watch is for you? Consider these three objectives.
Becoming more active
One of the well-known benefits of fitness tracking is simply to encourage movement. You wear an object whose main purpose is to record and analyze activity. When you are moving outside, GPS watches use a process called "triangulation" to determine your location and speed by using how long it takes to send and receive satellite signals and how far away the satellites are. When you are running indoors, walking, or staying still, GPS watches use accelerometers that detect movements or vibrations of the body to make similar determinations.
Fitness tracking can tell you how many steps you have taken in a day and even notify you when you’ve been sitting for too long. There is not a lot of evidence that suggests fitness tracking improves long-term health outcomes, even if they are good short-term motivators. When they became popular in the mid-2010s, surveys found that more than half of people who bought a fitness tracker eventually stopped wearing it. Keep in mind these studies were not just of runners, who are likely a more determined subset, experiencing both short-term and long-term benefits of tracking their runs. For me, GPS watches are more than just step counters. I’m often inspired to round up my miles for the day or pick up my pace for the sheer satisfaction of seeing a number on my watch!
Capturing reliable data
For the most part, GPS watches do a fantastic job collecting data. Factors such as winding roads, tall buildings, and even overcast skies can affect satellite signal acquisition and strength, but watches use multiple networks, higher signal refresh rates, and historical data about your running dynamics (e.g. stride length, stride rate, vertical oscillation) to overcome these blockers and track your miles. I’ve appreciated how most GPS watches today pre-cache satellite information so you wait only a few seconds to acquire a GPS signal -- a blessing when you are waiting outside in the cold or want to squeeze in a short run. And as I do most of my training on my own, my watch often acts as my training partner to keep me honest.
Many elite marathoners train with GPS watches but do not use them during a race, which is not surprising since when you’re competing at that level, tactics matter more than pace. Boston Marathon champion Des Linden says "satellites can be fussy in cities" and, like Kara Goucher, she prefers taking manual splits at mile markers. But for the rest of us, GPS watches can help keep us on pace in a race. When runners complain about GPS watches overestimating the length of a 6.2, 13.1, or 26.2 mile race, more often than not, the extra mileage is a result of not running the tangents around the corners along the course. Races are measured by the shortest possible route, which is nearly impossible to achieve in races with turns.
If you are training for a race, chances are you want accurate distance tracking and instant feedback on your pace. GPS watches are superior in this respect to most fitness trackers, smartphones, and smartwatches and tend to have longer-lasting batteries, which can make a difference for endurance races. Over the last few years, GPS watches have incorporated the capabilities of fitness trackers, but time will tell if smartwatches like the Apple Watch can reach the same level of accuracy and user experience as running-specific GPS watches.
Turning insights into action
Most of the information a GPS watch gives us is something we already know or can calculate with a stopwatch, even if it’s time consuming; nevertheless, the insights can help form an action plan for yourself. As a runner, I use lap pacing for instant feedback and to train faster during interval and tempo runs. I look at my history to do better next time or even just for a confidence boost before a race. As a coach, I study heart-rate data to comprehend an athlete’s effort and potential, and running dynamics data to work on running economy, remembering to take the data with a grain of salt. The latest GPS watches will even learn about a runner’s performance over time and predict race results or make recommendations on recovery time.
On the other hand, there is research that suggests you know yourself better than any high-tech device. We are more sensitive to physiological change and have a higher degree of consistency amidst environmental factors. Improving your ability to speed up or slow down based on immediate and intuitive feedback can be powerful. You know how to master your body, adapt your pace, and better respond to changes in a race. The extra step to check your watch while running can not only result in misleading decisions but also remove you from a feeling of control and state of “flow.”
Perhaps the most useful way to act on data from GPS watches is in aggregate. Millions of data points can form valuable statistical samples to optimize training programs, racing strategy, and even other areas like gear and nutrition to make us faster and fitter. One recent study used GPS data from Strava to validate the hypothesis that Nike's Vaporfly shoes can make you 4-5% faster. I’ve personally used my data in aggregate to better understand my fitness performance over a year and set goals for the following year. Some of the actions I have taken include incorporating strength training more regularly and including swim drills to improve my average swim pace.
My take
A GPS watch is worth it for the convenience and the insights, but use it thoughtfully! Focus on the data that will help improve your running, especially when you can step back and see longer-term patterns in your performance. And on most of your runs, ignore your watch. Pay attention for interval runs or occasional tempo and hard long runs. Running not only challenges us mentally and physically, but also instills a sense of freedom and joy that can be lost if we are constantly checking how far or fast we are running. What your watch tells you can never be a substitute for what you feel and what you want to do.