On Sunday the 23rd of April, the London Marathon 2017 arrives with the capital ready and waiting for all of you eager runners. The question remains however, will you be ready for it?
Even if your fitness is not quite up to scratch, you can arrive with the correct tech to inform you of your performance; this includes your pace, heart-rate and time taken. As well as pure functionality, our list also discusses the style of each of these designs. Even if you are showing signs of fatigue, you can still look cool.
You do not have to be participating in the London Marathon on Sunday to find this list useful, perhaps you will find yourself inspired by the brave and determined souls, and you will want to set you sights on the next one. Either way, this is the list for you.
Fitbit Surge
This fitness device heralds from a very well-known name in the space, to the point that I have heard the occasional person refer to wrist-worn fitness devices in general as ‘Fitbits’.
A snapshot of noteworthy aspects of this device includes built-in GPS, a heart-rate monitor, and the capability to work with the majority of phones.
The Fitbit Surge has a 1.25-inch screen, which when compared with many other similar devices is quite large. The display is also backlit, works on an always-on basis, meaning 
that you are more easily able to track the miles of road you have beaten on your quest to the finish line, and glory.
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Control is another strong point with this device, as the user is presented with a mix of touchscreen alongside three physical buttons. Physical buttons can be much easier if you need to manipulate the device amid marathon chaos, sweat and all.
In terms of aesthetics the watch is quite a clean design, with a simple square interface, and a textured, rubber strap. This may be considered as either being too much of a simple look, or even a bit too retro, but it fits in with current styles.
The device is a solid competitor, and could be considered to be on the no frills side of things, as it is not in colour, but who needs colour when the only one you will care about is that of the finish line.
Price average: £137.99
Garmin Forerunner 920XT
Streamlined does not enter the equation with this fitness device, it is a beast. Even by design the Forerunner 920XT is robust, big, and eye catching. While these aspects could be cons for one set of people, they are massive pros for another.
To go with the imposing appearance of the watch, it is also widely reviewed as being among the most powerful options too. Pitched as being suitable for a triathlon, the watch can easily take as heavy a beating as you can.
The real power of this watch is that it does not stop monitoring you when the exercise is 
done; it also keeps tabs on your daily steps, and even your sleep.
The device alerts you when you should be back on the move, and with social connectivity and GPS, it keeps your competitive motivation up by plotting your stats against friends and others.
Unfortunately a further element that makes the Forerunner a more bulky package is the heart-rate monitor that is separate to the main device, unlike the Fitbit Surge. However, the power of the device comes up trumps again, boasting a more detailed and vibrant display than that of the Surge.
The conclusion on this one really comes down to personality, if you do not mind the bold look and hefty design, and what you truly want is the massive power, this one is probably the one. If sleek, unassuming, and low fuss is the name of your game, perhaps look into the Fitbit Surge.
Price average: £330
Mio Fuse
The Mio Fuse is completely different to our first two options on the list, as its design is very much different from what you would ordinarily expect from a fitness device, with a look more akin to a wristband than a watch.
This device may be the perfect option for the hardcore runner that will not be phased by matters of style, as the Mio Fuse is heralded as having very high level heart-rate monitoring capabilities.
Another important area for the serious runner that this device has covered is battery life. It also works very well with other apps and devices, removing the annoyance of 
incompatibility.
The simple black silicone band has raised eyebrows for some, but could be considered extremely cool when matched with the red LED dot display, giving you a touch of the Terminator about you when you warn that Marathon that you will be back next time.
In addition to a mean look, the dot display has been considered an effective way of monitoring the necessary information such as heart-rate, time, and pace.
There are buttons on either side of the watch, that are not entirely physical ones, they are considered touch-capacitive. Another button is situated towards the middle. Another attractive feature of this watch is the price, compared to some of the other options.
Price average: £60
What about the Microsoft Band 2?
Microsoft Band 2
There are some really impressive details surrounding this device, and lots of noted improvements on its predecessor. Design is a major plus with this one, and the person most suited to this device will be the person looking for functionality.
A foremost noteworthy improvement with the second edition of the Band is simply how it fits the wrist, receiving solid reviews on the high level of comfort when wearing the watch.
Another really interesting feature is the presence of yet another sensor, a barometer, and if you do not know, it is for the measurement of atmospheric pressure. This will be handy when you are running up mountains, but could also be interesting when weaving your way through the London Marathon.
This device has many of the pros of the Fitbit Surge, but this one may sway some potential buyers with its colourful touchscreen. Despite this, it still does not achieve the sleek design of the Surge, being comparatively cumbersome with its large curved screen.
The device should prove tough, with Corning Gorilla Glass 3 protecting the AMOLED screen, upon which notifications are reviewed as being very easy to see and keep track of.
Price average: £170
READ MORE: Best Android Smartwatch: Top 5
Polar M400
No frills, no breaking the bank and leaving you fit but penniless, this one is the all-rounder. Some of the other options have been in the Marmite category for fitness devices, but you would be hard pushed to justify any seething hatred for either the design or the performance of this watch.
The device provides excellent run tracking and an accurate heart-rate monitor and is very good value for money. So when it comes to running a marathon, this sensible option has you more than covered.
Perhaps the most major downside, this watch is not an all in one, it incorporates a heart rate monitor that must be strapped to the chest. Despite this slightly cumbersome factor, it should not trouble someone whose main goal is effective feedback on performance.
The battery life is highly respectable, lasting for around eight hours with the GPS activated. The design is middle of the road, purely functional, and so is the display in the form of a monochrome, dot layout.
Price average: £99.99
