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Whether you’ve just decided to take the plunge and invest in your first wearable GPS device, or if your Forerunner 910XT isn’t cutting the same sleek silhouette on your wrist that it did in 2011, this article is here to guide you on the Garmin Forerunner series and help you determine the best fit for you.
What all Garmin Forerunner watches do as standard
At a bare minimum, all Garmin Forerunner models will be able to utilise GPS, Glonass, and Galileo global navigation satellite systems (GNSS) to allow you to record your distance, time and pace on a run.
They all possess an Elevate optical heart rate sensor, which gives very reliable resting heart-rate data and sleep tracking, and all feature ANT+ and Bluetooth connectivity which can be used to pair the device with an electrocardiogram (ECG) heart rate monitor mounted to a chest strap (amongst other external sensors).
When used with either the onboard optical heart rate sensor or when paired with a chest strap, all the current Forerunners will track your running VO₂ max estimate. Your VO₂ max is the volume of oxygen you can consume per minute per kilogram of body weight at your maximum performance, and is a great indicator of athletic performance in endurance sports. The estimate feature on Garmin watches, while not as accurate as a lab test, is a really useful way to track your increasing or decreasing fitness levels - it’s a relative measurement to you.
Additionally, all of these watches will allow you to record indoor and outdoor bike rides, pool swims, and track your steps and calories burned in a day.
Sporting wearables have come such a long way over the past 10 years. Even the entry level Forerunner 55 now wildly eclipses the old mid-range 235 in all categories - it delivers more activity profiles, greater functionality, longer battery life, a sleeker display, and all in a lighter and more aesthetically pleasing package. It’s pretty much on a par with the outgoing mid-range model, the Forerunner 245.
So how do you choose? Which one is right for you?
Let the type of running you do choose the watch
A running watch is an investment, not only a monetary one, but also of time. The watch you buy today will probably be the one you’re using two to three years from now, so think about your long term running goals when purchasing.
A fuss-free GPS watch that does the basics excellently
Choose the Forerunner 55. While it’s the entry level option of our current Garmin range, it boasts a 20-hour battery life in GPS mode. A couple of generations ago this kind of battery life was only available on the premium multisport Fenix range.
And while it’s a relatively simple watch, the features it boasts and the metrics it records means that there’s room for you to grow into it as and when running or metrics start to become a bigger part of your life.
A triathlon-capable watch with enough battery to handle an Ironman
Your options start at the mid-range Forerunner 255, which comes in a standard version and a music version (the 255 Music is identical except for being capable of storing music). These come in ‘S’ models (the Forerunner 255S and 255S Music) which are smaller-sized to fit smaller wrists.
On previous generations of Garmin watches, being able to record open water swimming, and link the three disciplines and transitions into triathlon mode, was reserved for the top-end Forerunner 945, the triathlon-focused 745, and the Fenix range. This has now been rolled down to the Forerunner 255, which also boasts up to 25-hour battery life on all satellite systems mode and 30 hours in GPS mode, against its predecessor’s 12-14-hours (24 in ultratrac mode).
This mid-range watch also features multi-band GPS. On previous watches, you could select GPS+Glonass or GPS+Galileo under run settings, but with multi-band, you can select to receive simultaneous reception of multiple GNSS across multiple frequencies (older models used only one frequency).
If your GPS tracks are frequently blighted by tall buildings
Big city dwellers now have a range of options featuring multi-band GPS, starting with the aforementioned Forerunner 255.
For more information on how multi-band works and how it came about, there’s an informative interview with Garmin engineer Jared Bancroft to read, but fundamentally, it means increased accuracy from your watch - even in urban areas dominated by tall buildings and even running around parks where there’s a lot of tree cover. This feature is available on the Forerunner 255, Forerunner 255 Music, Forerunner 955, Forerunner 955 Solar, and the Fenix 7 range.
If your training is all about the numbers
The Forerunner 255 and 955 (and their variants) now feature semi-native running power. Previously, getting running power onto your screen involved going through Garmin’s Connect IQ app, but now it just requires pairing with the Running Dynamics Pod and you’ve got plug-in and play running power on your watch.
Power has become the gold standard for measuring intensity in high level road cycling and is in the early stages of making its way over to running. It becomes especially useful for measuring effort on climbs and running into the wind, as it is purely looking at your output, rather than what pace the conditions are allowing you to hit on workouts.
Both these watches also feature nightly heart rate variability (HRV) tracking. It requires you to have worn the watch with the optical HR sensor turned on for 19 days, as it is tracking this metric as a long-term trend.
In short, HRV is the variation in time between heartbeats. If your resting heart rate is 65 beats per minute, those 65 beats will be occuring at intervals of varying lengths. The greater the variability between those 65 heartbeats the more “ready” the body is to perform at higher levels.
HRV is widely regarded as one of the best objective metrics available to athletes in determining their physical readiness to perform.
A watch that can do everything in a lightweight package
The Forerunner 955 is the answer. This is the update from the Forerunner 945, nicknamed “the plastic Fenix” because it did almost everything the Fenix did, but came in around 30 grams lighter.
The 955 packs in all the features of the new 255, plus plenty extra - from a running perspective, this does everything a sports watch is capable of, and provides you with every bit of data you could conceivably want.
In GPS mode it will last for up to 42 hours, and in all satellite systems mode it will last for up to 31 (20 hours in multi-band mode), so while nearly all Garmin watches are up to the duration of large ultra runs, few are quite so capable as the Forerunner 955.
Adventurers, mountain runners, and ultra trail enthusiasts
Choose the Forerunner 955 or consider a Fenix.
The majority of Garmin wearables have inbuilt navigation features designed to point runners in the right direction, but if you’re one to purposely get far from civilization and venture into remote locales, you’re going to benefit from a watch with full topographical mapping and a screen size to match.
These watches also separate themselves from the 255 by featuring Climb Pro, a feature in the trail running activity profile that shows you your progress through major climbs in real time. It should be noted that if you train with a focus on elevation, and have no need for navigation features, the 255 has added a barometric altimeter to allow you to see your vertical gain in real time, mid-activity, unlike the 245 it replaces where you would have to wait until after your run to see how much climbing you’d done.
The Forerunner 955 Solar (as the name suggests) is a solar-powered version.
For the music enthusiasts
If you want phone-free music on your watch to pair with some Bluetooth headphones, you have the Forerunner 255 Music, the Forerunner 955 and 955 Solar to choose from.
You can store approximately 500 songs on the Forerunner 255 Music, up to 2,000 songs on the Forerunner 955 and 955 Solar. You can load MP3 files onto the music compatible watches, or, far more simply, you can upload albums from a Spotify Premium account by Bluetooth.
Playing music during an activity does result in a battery hit. The Forerunner 255 Music will last for up to seven hours in GPS mode with music (versus 30 hours without) while the Forerunner 955 and 955 Solar will last for up to 10.5 hours in GPS mode with music (versus 42-plus hours without).
