The days of simply tracking your fitness progress with a stopwatch and notebook are officially over; no self-respecting amateur athlete would be seen out in the gym or on a track without a decent fitness watch. The price of these gadgets can vary greatly from $60 to $300, but the Polar M400 GPS Sports Watch sits somewhere near the middle. Overall, this is a good investment for those who are enthusiastic about their fitness above all else.
The Polar M400 can give you data on your heart rate, pace, calories burnt, ascent and even altitude. The watch is predominantly used for running, walking, and day to day activities, as it tracks activity through wrist movements. The watch is waterproof so you can even take a swim (although you will be unable to track your heart rate in the water),
It can also track other activities such as yoga, weight-lifting and cycling when paired with a heart rate sensor, but it won't accurately measure these activities on its own. For measurements on these activities, you'll have to turn to the M400's older sibling, the V800 - but it comes with a much heavier price tag.
Overall, the GPS and heart rate monitor are incredibly accurate for a fitness tracker, as is expected from the Polar brand, but nothing can replace a chest monitor such as the Polar H7 for accuracy. It may take a little while for the GPS tracker to find it's location, which can be frustrating to fast-paced runners, but once it does it delivers smoothly.
The battery life on the M400 beats out the most popular fitness trackers for continuous day-to-day wear, advertised to last for 30 days. When the GPS and heart rate monitor are used actively, however, the battery life dwindles down to 8 hours - enough for a beginner to run a marathon, but just barely.
The face of the watch can be customised to your liking plus it sets you daily motivational goals to get you up ad about even on your lazy days, as expected from a fitness tracker in this price range.
The Polar Flow App is nothing pretty, but what it lacks in good looks it makes up for in functionality. When synced with your laptop, the device provides visual representation of your sleep, daily activity, heart rate zones, maps based on your GPS location, and even suggest future workouts for you based on distance and heart rate triggers.
The Polar M400 may feel bigger and more awkward than other fitness trackers, and lacks a the slick LED screen of a smartwatch. If you want a subtle, sexy accessory to wear day-to-day in the office, this is not it. However, it packs more fitness-focused features into it's bulky frame than any of it's competitors, so if you're more serious about working out than looking good, this will suit you well.
The Before-You-Buy Takeaway:
For runners and semi-serious athletes, the Polar M400 packs the biggest punch for it's price: a heart monitor, GPS, a waterproof body, long battery life, as well as step counting, sleep monitoring, goal-setting, and all of the basic features that we have come to expect in a fitness tracker. The downside; it can be a little clunky to wear and to use, and it doesn't provide accurate activity measurements for hardcore weight-lifting, cycling, or swimming. But overall, when it comes to function over fashion in it's price range, it can't be beat.