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Garmin’s Forerunner fitness trackers have long been one of the brand’s most popular among serious runners. Not only do they offer unique running data and tailored feedback but they’re designed to fit, feel, and function exactly the way a runner needs it to.
Garmin’s first Forerunner was called the 101 and debuted in 2003. After dozens of technological generations and improvements over the years, the latest is the Forerunner 935.
To truly put this advanced running watch to the test, we had competitive distance runner, Ted Westbrook, put the 935 through 1,000 cumulative miles of running. Westbrook has over a dozen years of experience using GPS running watches and is no stranger to utilizing fitness trackers in his training.
After three months of using the watch — both in training and in races — Westbrook told Insider the Forerunner 935 is “far and away the best training tool I’ve ever used.” Below is a closer look at Westbrook’s experiences with the watch to see just how impressive it actually is and if it truly is one of the best fitness trackers available.
A mid-size watch with premium features
The Forerunner 935 is a mid-sized watch for the average man and a large watch for the average woman. It is, however, lightweight (49 grams), comfortable to wear, and packed with features. The band, which is made of a slightly stretchy rubberized plastic, is an improvement in comfort over its predecessor, the 920XT. It also looks nice in the dark gray color.
The face is protected by tempered glass that’s very scratch-resistant — another substantial improvement over the 920XT. The watch offers a battery life of up to 24 hours with GPS enabled.
In addition to providing real-time feedback like pace and distance, the 935 also features an integrated optical heart rate monitor that proved to be both accurate and quick. This allows you to glance down and get a useful indication of how hard you’re working. Many runners can benefit from setting target heart rates, too, particularly for easy-effort runs where the goal is active recovery and not to over-stress the body.
The 935 is also waterproof to 5 ATM and has a mode entirely devoted to swimming, is able to keep accurate stroke counts. Cyclists will appreciate being able to use it as a cycling computer, as it has devoted outdoor and indoor cycling modes and the ability to connect to ANT+ bike speed and cadence modules. There’s even a dedicated triathlon mode that tracks each leg, providing custom information for each sport, along with transition times.
It has a built-in barometric altimeter to provide irrefutable scientific confirmation that your last run was hillier and more extreme than your friend’s last run, or that your combined elevation gains for the last year would get you to something like the International Space Station. Though it has the flair of some of the best smartwatches, all of these features show that it’s a fitness tracker through and through.
It offers a wealth of fitness metrics at your fingertips
The Garmin Forerunner 935 collects and displays all your workout data, and allows users to customize the face to show exactly what they want. While running, you’ll want it to show three or four different parameters at a time so each is readable. For instance, you might want lap pace, distance, and heart rate on one page. The 935 allows great customization so that you can move your chosen parameters to where you want to see them and add or remove data screens.
Westbrook loved this functionality: “I have one screen that I use most of the time and a second that’s available at the push of a button for data that’s more specific to running interval workouts, like lap time and lap distance. Customization is easy and intuitive.”
It’s highly accurate both with and without GPS
Whether on an indoor track or treadmill, the watch maintains solid functionality via indoor running modes that use the watch’s precise accelerometers to estimate pace and distance. While generally less accurate than using GPS outdoors, Westbrook confirmed that the non-GPS mode still provides accurate data to within 2-3%, which is remarkably good.
Many of the 935’s advanced features are more accessible post-run through the Garmin Connect system, which is available as a mobile device app and a web interface. This is where the 935 is unique. It allows a serious runner to truly geek out on data analytics while enjoying a post-run beer in the supine position.
The 935 takes heart rate, pace, and distance data and combines it with information about your height, weight, age, sex, maximum heart rate to estimate your VO2 max and lactate threshold — the two most important metrics of running fitness and potential. It can also tell you how stressful your run was for your anaerobic and aerobic systems on scales of 0 to 5.
Taking data over time into account, the 935 and Garmin Connect can give indications of whether your overall training is productive or unproductive through the Training Status feature.
It’s not a perfect watch and does have a few drawbacks
Many, if not all, of the advanced training functions of the 935 and Garmin Connect rely on assumptions and formulae that aren’t always going to produce accurate results. At one point, the Race Predictor feature of the 935, relying on calculations of VO2max from Westbrook’s running and personal data, predicted that he could run a marathon in two hours and 28 minutes.
Westbrook told us, “This was flattering but about 7% faster than reality.” VO2 max can only truly be measured in a lab environment.
By the same token, even the formulae are subject to user-induced error. For example, it is important to have accurate weight data. Westbrook shared with us a recent experience where the watch told him that his lactate threshold pace had worsened by a few seconds per mile after a moderate run while pushing his baby daughter in a running stroller on hilly terrain.
“The watch just can’t correct for that added effort,” Westbrook said. “It can only assume you’re having a bad day or are getting old, which I am not.”
With all of the advanced data available — which is often most useful for high-mileage competitive distance runners who are out on the pavement or track every day — it’s fair to question whether a new or occasional runner should go for a lower-shelf model than the Forerunner 935. It may also be worthwhile to consider a different fitness tracker like one of the best Fitbits or one of the best Apple Watches if running is only one of many activities you plan on doing.
While the answer could depend on one’s budget and just how much of a runner they want to be, new runners are likely to appreciate how well the 935 does the basics of near-instant GPS acquisition, pace, distance, and heart rate. When they’re ready, the more advanced data analytics would still be there when they want them.
A beginner isn’t going to outgrow the 935, and the basics are intuitive enough in use that they won’t intimidate anyone who is used to dealing with smartphones. The 935 is an investment that pays dividends in fitness motivation and hardcore data.
Unlike other previous models, like the Forerunner 745, the 935 does not have the ability to store music from Spotify or other sources, though this isn’t much of a problem if you already use another device for that purpose.
Should you buy it?
Yes. Whether you’re a competitive runner or just want to improve your fitness and cardio, the Garmin Forerunner 935 is a worthwhile investment.
Caveats notwithstanding, the 935 is a running geek’s dream come true. It works in competition and training, plus it gives a huge array of analytics to inform your training approach. Much like the Forerunner 745, it doesn’t fail to impress experienced athletes.
We asked Westbrook if he would continue to use the 935 once done testing it. He said, “Most certainly. And, I would buy another if this one got lost.”
