Whether you're going for a big long run in the park on your lunch break or decided to sign up for an Iron Man, triathlons require lots of intense training that will push your body to the limit. If you thought marathon training was hard, this is a whole new level of putting your body through agony.
Thankfully, you don't have to put in the laps and miles completely alone. There's plenty of wearable tech to give you a helping hand during those early morning or lunchtime sessions.
Fitness tips: How to use heart rate training zones
From GPS watches to body suits, we've sifted through the best and worst of the kit to help turn you into a speedy swim-bike-runner.
Here's our top triathlon tech picks to help you be, ahem, tri-umphant.
Garmin Forerunner 920XT
Until we get to spend some more time with the new Forerunner 735XT, the 920XT remains our pick as the go-to Garmin watch for multi sport action.
Wareable verdict: Garmin Forerunner 920XT review
The wetsuit-friendly timepiece tracks your pace, distance and when you dive in to the pool your stroke count and rate, too. If you're willing to spend a little more, you can always consider the Garmin Fenix 3 as well.
TomTom Spark Cardio + Music
The new TomTom sports watch, which now includes a built-in music player, still packs QuickGPSFix tech picks up your location faster and increases accuracy. So your results are much more precise, a must for keeping a track of your progress.
Full review: TomTom Spark Cardio+ Music review
Real time information, whether you're running, cycling or swimming is displayed on the roomy screen while the new slimmer design won't weigh you down either. It won't supply with you the same detailed metrics as a Garmin, but it's a decent choice for someone who's starting to think about venturing into the triathlon training world.
The V800's headline feature is its fantastic coaching system, which is ideal if you're just starting out your triathlon preparation. With the Polar Flow service, you can create tailored profiles for each sport, balance your training and recovery plus analyse even the most minute details.
Wareable verdict: Polar V800 review
Integrated GPS accurately tracks your runs, while pairing it with a heart rate monitor strap means it works when you've hit the pool.
Garmin Vivoactive HR
Much like the TomTom Spark, the Vivoactive HR could be a a good introduction to someone that's starting to think about venturing into the world of triathlons and wants to track more than one sport.
Wareable verdict: Garmin Vivoactive HR review
There's an optical heart rate monitor on board and GPS with dedicated apps included for cycling, swimming, running and a whole lot more. It also supports Garmin's Connect IQ apps so you can additional data fields and features. With solid battery life, it's definitely one to consider.
While we still put the Suunto Spartan Ultra through its paces, the Ambit3 is still a great watch for you triathletes. It beams all the data it captures from multi sports directly to a fantastic iPhone companion app all in one log.
There's a compass, speed, pace and distance tracking and it'll give you an activity based recovery time so you can tell when you should take a rest day. The heart rate monitor can also be used when you're swimming, while the tailored training programmes are great to keep you on track.
VRX MP3+ Personal Trainer
This duo of products gives you an underwater MP3, Real Coach training tips that will talk you through your swim as you're putting in the laps. You can even build custom workout plans to mix training sessions up.
Best of all, there's a silicone swim case that'll keep everything protected underwater so you can take them for a swim.
SKINS TRI400 Compression Tri Suit
The Skins Dynamic Gradient Compression delivers oxygen faster to your muscles, giving you more power. Recovery time is improved too, as lactic-acid build up is reduced.
The Toray fabric minimises drag, ideal for both the water and road, while integrated UV protection and moisture management make this the perfect fit for hot, sunny days.
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