Nix Hydration Biosensor overview: for the athlete who sweats the main points

All over the place I look, individuals and devices are yelling at me to hydrate. On social media, the algorithm bombards me with health and wonder influencers who say I ought to drink a gallon of water a day. (Glowing pores and skin! Shed that final cussed 5 kilos! Extra vitality!) The varied smartwatches I take a look at all have these hydration widgets for monitoring my every day water consumption. Not too way back, I had a “sensible” water bottle that flashed hourly rainbow LED lights as a reminder to drink up. Most just lately, I’ve been sporting this little pod on my bicep. It, too, tells me to hydrate — however in a approach that’s surprisingly helpful.

The $129 Nix Hydration Biosensor is a pod-and-patch combo that alerts endurance athletes when they need to hydrate throughout a exercise. It claims to present customized hydration suggestions, in addition to calculate your particular person electrolyte loss relying on sure elements like climate and sweat fee. It’s overkill. Hydration doesn’t want to be this costly or difficult. However for knowledge nerds and endurance athletes, the Nix sensor does provide some sensible steering that, for some, could be definitely worth the value.

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Simpler to make use of than Gatorade’s sweat patches

A couple of months in the past, I examined the Gatorade Sensible Gx bottle and the Gx Sweat Patch. It was one other gadget-patch combo that claimed to learn your sweat within the identify of extra clever hydration, however I wasn’t a fan. Not solely did it really feel like a automobile to promote me extra Gatorade, the sweat patch by no means labored for me. It left me cautious that the Nix sensor would even be a tool that was higher in idea than execution. However whereas the merchandise are comparable, Nix delivers a greater total expertise.

The Nix sensor has two parts: a reusable sensor pod and single-use patches. The patches are manufactured from a latex-free adhesive that’s snug to put on. It jogs my memory of KT Tape in that it’s versatile sufficient to maneuver with you however sticky sufficient to not slide off your pores and skin once you begin sweating. The patches are small (2.75in diameter), and I didn’t have any difficulty becoming it on my bicep. Earlier than a exercise, all it’s a must to do is align the pod with the grooves within the patch’s sensor attachment and twist till it locks in place.

Close up of the hexagonal Nix sweat patch showing area where pod sensor clips in.

The patches have an attachment the place you clip within the Nix sensor pod. You then peel off the backing and slap it in your bicep.

Close up of the back of the Nix Hydration Biosensor pod

The again of the sensor pod. To lock or unlock it from both the charging case or patch, you align the grooves and twist.

Whereas the sensor and patch had been straightforward sufficient to put on, the large take a look at was whether or not it’d have the ability to learn my sweat, particularly since I’m testing this within the winter. Not solely do I sweat much less in winter, however I’m not a type of robotic runners who can log 10 miles within the freezing wind in nothing however a T-shirt and shorts. Apart from sweat detection, I used to be curious to see whether or not the sensor would catch on my lengthy sleeves or if sporting a number of layers would trigger any points.

Apparently, my bicep is sweatier than my forearm, and it made a distinction. In accordance with Nix, the bicep is likely one of the finest locations to estimate your complete bodily fluid and electrolyte loss whereas delivering a superb consumer expertise. (Gatorade’s patches go on the forearm, and neither patch is validated for different components of the physique.) On three out of 4 take a look at runs, the Nix sensor was simply in a position to get a studying. I’ll get into my botched run beneath, however I guarantee you it wasn’t as a result of it couldn’t detect sweat. As for my sleeves, I didn’t have any issues apart from after I needed to reconnect the sensor after already placing on my shirt. All meaning is, in winter, you’ve acquired to watch out to ensure all the pieces’s linked earlier than you head out.

Nix additionally makes it simpler to add and sync knowledge. It mainly works like several smartwatch or health tracker. While you’re achieved with the exercise, you finish it within the app, await Bluetooth to do its factor, and voilá. Knowledge seems. (Syncing can take a scorching second, however that’s commonplace.) You are able to do this with the patch on or off, too. Conversely, Gatorade makes you snap an image of the patch, and the entire system depends on analyzing the sweat-activated ink sample on a used patch, which, if you happen to’re not sweaty sufficient, received’t work. Even if you’re sweaty sufficient, generally you’ll need to retake the picture as nicely.

One other factor I appreciated was the charging case. It may appear too huge, given the scale of the pod, however I really like that. I’ve used and misplaced loads of foot pods and different small wearables with small circumstances. That is large enough to simply discover, whether or not it’s on a nightstand or stashed in a bag. Plus, the lid has a slot the place you possibly can stick a patch for comfort. And since it’s a charging case, you don’t actually have to fret concerning the battery. The sensor pod lasts 36 hours on a single cost, however as long as you’re placing it again within the case once you’re achieved, you received’t have to fret about it for a couple of months.

Picture of Nix charging case and sensor pod side by side.

This charging case may appear huge given the how small the sensor pod is, nevertheless it additionally makes it more durable to lose.

Nix additionally supplies real-time hydration alerts. This was a hit-or-miss function for me for the reason that alerts principally come from the Nix app in your cellphone. If I had the Nix app open and on display screen, the alerts had been extra noticeable. If I made a decision to have one in every of my many different health apps open, I tended to overlook them fully. You’ll be able to choose to get them in your Apple Watch or certain Garmin smartwatches, however once more, I’ve personalized my exercise views to point out me precisely what I need to see, so this wasn’t my favourite choice. Plus, the app warns that it could take about 25 minutes earlier than there’s sufficient sweat for the sensor to learn, nevertheless it might additionally take a bit longer. Throughout one take a look at, I didn’t see any related knowledge till 35 minutes into the run and continually checking took me out of the zone. I like distraction-free working, so I most well-liked reviewing my knowledge after a exercise after which making use of what I realized to the subsequent. However, on the danger of dogpiling on Gatorade, a minimum of you’ve gotten the choice for real-time alerts if you would like them.

Connectivity might be higher

Whereas the Nix sensor wipes the ground with Gatorade’s sweat patch, there are some downsides. For me, the largest one is connectivity. Whereas I didn’t have a lot bother with the sensor’s Bluetooth throughout setup, it crapped out on me twice throughout testing. A kind of occasions was fairly minor. I’d already completed an hour-long run after I seen the sensor had misplaced connection to my cellphone. As a result of I used to be dwelling, I used to be in a position to take the pod out of the patch and reinsert it earlier than getting within the bathe. The whole lot reconnected, downside solved. I used to be additionally nonetheless in a position to add my knowledge.

The second time was my botched take a look at run. I had put a totally charged pod right into a patch, accurately positioned it on my bicep, acquired dressed, laced up my footwear, began up all my different wearables, and… forgot to hit begin within the Nix app. (It was early, and I’m not a morning particular person.) I didn’t discover my goof till midway by means of a 105-minute future. I attempted to begin a belated exercise — some knowledge is healthier than no knowledge, proper? — however the pod wouldn’t hook up with my cellphone. This was regardless of the actual fact I might see the Nix was on, and if LED indicator lights are to be believed, working. I attempted twiddling with the sensor, locked and unlocked the sensor by means of my sleeve, turned my cellphone on and off, after which tried turning the pod on and off. No luck. I attempted the entire rigamarole a couple of extra occasions later within the run, simply in case it was my location. Nada. It wouldn’t reconnect to my cellphone till I used to be again dwelling. At that time, I attempted to see if it might add my sweat knowledge however no luck there, both.

I made a foolish mistake, however not an implausible one

That royally sucked. I missed out on invaluable long-run knowledge, and lengthy runs are when hydration is most necessary! Even worse, these are single-use patches, and I’d wasted one. It prices $25 for a refill pack of 4, that means every patch is $6.25. Human error performed a big function on this, however higher connectivity might’ve a minimum of saved the scenario. I made a foolish mistake, however not an implausible one.

I get why the sweat patches are single-use. Adhesives by no means stick fairly as nicely after the primary time. Plus, you’d have to clean off previous sweat for correct knowledge, and adhesives break down with water and cleaning soap. However figuring out this doesn’t cease these patches from feeling wasteful — each monetarily and environmentally. Nix does have a partnership with Terracycle, so you possibly can a minimum of recycle used patches totally free. I admire the choice, however I needed to root by means of Nix’s FAQs to even discover out about it, and the entire course of requires a bunch of additional steps. Persons are lazy, and I’ve a sense most used Nix patches will find yourself in a landfill anyway.

Close up of Nix sensor pod with the green indicator light up top on.

The sensor has a inexperienced LED indicator gentle so when it’s on and dealing. Relying in your exercise clothes, you may also have the ability to see it by means of your sleeves.

Whereas I’m airing my gripes, it’s a bummer that the Nix sensor doesn’t help exercise varieties outdoors of indoor/out of doors working and biking. You don’t actually want granular hydration knowledge for yoga, pumping iron on the health club, or a brief HIIT exercise, nevertheless it’d be good for lengthy hikes, different sorts of strenuous cardio, or out of doors sports activities. Hopefully, Nix will add help for extra exercise varieties down the road.

I used to be additionally disillusioned to see Nix is iOS-only in the meanwhile. The corporate says that Android compatibility is slated for this month (February 2023), nevertheless it wasn’t accessible after I was testing the gadget.

Knowledge match for Kind A athletes

To get correct outcomes, Nix recommends a sweaty run or biking session that lasts a minimum of 45 minutes. When you efficiently log a exercise, the app spits out a abstract that features the train, whether or not it was indoors or open air, and what you used to hydrate. You’ll additionally see temperature, humidity, dew level, photo voltaic load, wind, and altitude. As for hydration metrics, the app will let you know how a lot fluid and electrolytes you misplaced in the course of the exercise, in addition to your sweat composition (aka, how salty your sweat is).

There’s additionally a extra basic sweat profile that aggregates knowledge from a number of exercises. There you possibly can see your estimated sweat fee, electrolyte loss fee, sweat composition, and Nix Index, a proprietary rating that’s meant to point out how sweaty a selected exercise was for you.

Person holding Nix sensor in palm with open charging case in the background.

I like how one can additionally stick a patch within the prime of the charging case’s lid.

Once I advised my partner about this, they gave me a withering look. It’s the identical one they provide me each time I clarify a brand new doodad I’m testing and the information it tracks. It’s derision incarnate. You see, my partner and I are polar opposites in the case of health knowledge. My partner is a type of naturally gifted athletes who handle to run just like the wind on 4 hours of sleep and a half-eaten protein bar. They solely begrudgingly use an Apple Watch to stream music as a result of they will’t be bothered with offline playlists. They’ve by no means as soon as reviewed their exercise stats. This sensor isn’t for easy-going Kind B athletes like my partner.

It’s for individuals like me, the Kind A doofuses that use color-coded spreadsheets for coaching logs and set out their exercise garments the night time earlier than. The nerds who lookup and evaluate a number of coaching plans and vitality goo vitamin labels earlier than deciding on one. Those who look within the mirror and suppose, “I, a quantified sicko, may be optimized for most efficiency.”


The app is pretty easy, however I discovered the hydration beverage chart useful.

I’m absolutely conscious that I don’t want Nix to run a well-hydrated 13.1 miles. I’ve run loads of races earlier than I ever tried Nix and have all the time crossed the end line in a single piece. However I additionally know I can do higher. I admire figuring out I sweat about 7.8 ounces of fluid and 365mg of electrolytes per hour within the winter. I like figuring out I ought to use a sports activities drink with roughly 47mg of electrolytes per ounce. You are able to do the maths your self, nevertheless it’s a headache. Sports activities drink firms don’t make it straightforward to determine and evaluate electrolyte ranges, and advertising and marketing tends to give attention to carbs as an alternative.

That’s why it’s cool that there’s a useful chart proper on this app I can reference that lets me evaluate electrolyte ranges of well-liked sports activities drink manufacturers. Seems Liquid IV is the one that almost all carefully matches my electrolyte wants. It’s not arduous proof, however anecdotally, my coaching has improved since I coincidentally made the swap from Maurtens a couple of months in the past. I’ll one hundred pc use this info after I’m making ready my subsequent future.

The underside line is it helps me plan my runs, which in flip alleviates my nervousness about finishing stated runs to my ridiculous and arbitrary requirements. If planning helps you are feeling extra assured a couple of run or a biking session, then there are a couple of eventualities the place I can see the Nix sensor being a worthy funding.

Close-up of the Nix sensor pod in profile view while attached to the patch on someone’s arm.

The sensor pod isn’t that thick, both, so it match comfortably below my lengthy sleeve tech shirts. Simply be sure that all the pieces’s linked and able to go earlier than you step out the door.

For instance, if you happen to’re a triathlete who incessantly races in all types of climates. The Nix might be useful in fine-tuning your hydration technique everytime you prepare in an unfamiliar setting. Or, if you happen to’re notably warmth delicate, this would possibly enable you enhance summer season mileage safely. Folks simply beginning to deal with longer distances might additionally profit. Personally, I’d have preferred a place to begin after I was new to hydration and fueling methods.

However paying $130 for a sensor and $25 for patch refills is quite a bit, particularly because you’re not going to be sporting a patch for each exercise. For most individuals, that is simplest as a benchmark instrument that you just escape when the climate, your setting, or your coaching regimens change. Somewhat further to present you a slight edge. That’s the factor about devices like these. They’re not important. They’re a “good to have” if, and provided that, the expense is sensible.

In the event you’re offered on the concept of hydration patches and making an attempt to resolve between this and Gatorade Gx patches — simply go along with Nix. It’s dearer up entrance, however in the long term, you get 4 patches in a $25 refill in comparison with two. It’s additionally extra thoughtfully designed, works reliably, and offers you extra actionable knowledge. It’s what Gatorade was making an attempt to do, however higher.