Polar M400 review

There is one product in particular which has become synonymous with fitness and sport – the GPS  watch. Whether you simply want m400-white-hrto track your daily activity or you’re a professional athlete looking for detailed training data, there are heaps of manufacturers developing a dazzling array of models, so the competition is hot.

I’ve been wearing the Polar M400 for over 2 years now, training for events including 70.3 triathlon and ultramarathon. Quite frankly, this watch is a stunning piece of tech and an absolute bargain! Polar have almost made a watch that’s too good for this part of the fitness market. Here’s why:


The best bits:

  • The main wrist unit has great build quality – after 24 months of significant use (both in the water, on the bike and running) there isn’t a scratch on the screen and the soft strap is as good as new – and still white!
  • £ for £ it’s a bargain – you can pick one up with HR strap for as little as £130!
  • It’s suitable for 99% of athletes with more features than you will probably ever use – I’m still discovering new ones.
  • Whether you’re into Street Dance, Telemark skiing or Les Mills classes – there’s a specific, customizable profile for it. Sadly my Street-dancing days are over.



Minor Cons

No Ant+ compatibility, but with Bluetooth now commonplace this isn’t such a biggie. Similarly, there’s no power meter data for the bike. If that’s something really important to you there are a host of bike-mounted units and watches aimed at the long course cyclist out there.

It’s no Fenix 3 in terms of battery life. I’ve used it over a 70.3 with full coverage, but if you’re racing 50 mile ultra-marathons or recording your full ironman you’ll need a more substantial unit.

Using the M400

Several of the athletes I coach have recently invested in the M400 and been very impressed.   It’s fully customisable in terms of data fields (below), HR zones, speed zones and watch faces.

Polar views

Polar use a great online platform to analyse your training data. It’s user-friendly, quick, visually-rich and most importantly it allows for easy analysis of your key sessions so you can plan future sessions and make those all-important fitness gains.


You can easily highlight areas of your workouts for further analysis, alongside your HR zones, elevation and speed data:

Polar analysis

Why buy it?

If you’re a runner, cyclist, triathlete, walker, (street dancer), or simply a gym enthusiast who wants accurate HR/workout data, then this is a product that will deliver on all fronts and at an unbelievable price point. Do not be fooled by it’s slightly under-stated looks – this is a serious piece of fitness kit. If you don’t believe me and you want to read more than 400 words from the review guru himself, DC Rainmaker’s review is here.

(One important point on modern tech reviews: many product review sites are out of date because products are often  released with future software updates – which can essentially unlock a host of new features. The M400 is no exception: BikeRadar scored it as a 3/5 because of no auto-sync with Strava or Training Peaks – but these are now fully integrated functions. Do your research carefully.)