LVL, a wearable hydration monitor, nears $1 million on Kickstarter

If only humankind had evolved some way to instinctively know when they require food and water, perhaps they wouldn't have faced extinction all those years ago

That was a very long and complicated way of saying "the very best the product can do is match the benefit of drinking enough electrolyte in the first place".

If you model the benefit of a system such as this, assuming it works perfectly - i.e. gives you an instantaneous, perfect measurement of hydration status - then it still does not and cannot give you any greater performance benefit than a buzzer that simply reminds you to drink at suitable intervals.   If you put any assumptions at all into the model about imperfect performance (delays in measurement, innacuracy and so on) then it cannot even achieve this!

This is because of the delay in between you taking in fluids into your mouth and them getting into the rest of the body.  No matter how perfect your sensor is, it cannot accelerate this process.

Hopefully I can help clear up some of this, as one of the guys very passionate about this product and helping out...

First, hydration levels (over-hydration, and dehydration) DO impact your health, performance, and nearly every aspect of your life. It's not as simple as people make it out to be, well we've lived this long without it, just go off "thirs" and "urine color". Hopefully people who say this have the same arguements against cars and would never consider buying one, due to having legs and feet :).

When you dehydrate, your blood volume drops (blood is highly concentrated of water), which is not only represented in blood, but tissue, which is also highly concentrated of water. As your blood volume drops, your heart rate increases to counter it, which is known as cardiac drift. Many distance runners can very easily see this graphed. We have studied many thousands of subjects over many, many tests, to identify conditions and complications that come from less than optimal hydration levels. Change is tough for some people, and some find it hard to believe if we've lived this long, why would we need this. Well, we DON'T NEED this, but like many other forms of tech that have come from science and study, which drastically increased human life expectancy (met with doubt) this is another big step.

Further, hydration isn't even just a matter of water, sweating causes sodium loss, which only drinking water will eventually start to provide no benefit:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2267797/

And more on thirst:

• Thirst doesn't typically do much for people drinking alcohol who are dehydrating
• Thirst doesn't tell you the volume of sweat and sodium loss or what volume to drink and if it's working. It's not just water you need, depending on your condition.
• Thirst doesn't tell you when you're 1.5 hrs into a 2 hour hike to camp and finished your canteen, if you are okay to finish, or need to find more water asap, or risk things as simple as headaches to much worse.
• Thirst doesn't tell you when your child that's out on the sports field, or elderly parent, is dangerously dehydrated.
• In high heat and high intensity exercise, you can lose multiple pounds of fluids via sweat in a matter of 20-30 minutes. You may barely be starting to feel thirsty, but be WAY beyond the point of being able to catch up.

If it were just a matter of thirst, you would rarely ever hear about the many conditions related to dehydration people suffer and die from. If someone is thirsty, maybe it's a good sign they should drink, but exactly HOW dehydrated are they at that point?

We're not saying you will die without this, or using scare tactics, but educating people is important. The fact is, there are many related imporper hydration complications, all the way to the point that people can and do die from hydration/heat issues:
http://kendrickfincher.org/kendrick-fincher-bio/

Our tech isn't a gimmick, we've proven it, with our last successful Kickstarter and device that reads muscle oxygen levels, used by many athletes. IBM Watson and US Olympic athletes use it all over the world:
https://developer.ibm.com/bluemix/2016/07/27/internet-of-things-wearable...
The device can be found here:
www.bsxinsight.com

It's also been 3rd party validated, by many, with no involvement by us. You can find it published in places like the Journal of Strength and Conditioning Research:
http://journals.lww.com/nsca-jscr/Abstract/publishahead/Wearable_lactate...

On top of the smartwatch features, and hydration levels, we have the highest standards of optical heart rate monitoring, with greater than 3bpm rms error. It's not your typical heart rate standard people are used to with optical tech. In simple terms, you can read the red light vs. green light article:
https://medium.com/bsxtechnologies/red-light-versus-green-light-74fdd5fe...

But what about looking at urine color for hydration levels? Some ask this, convinced of its accuracy. Well, it's something used by the military and they will tell you how much it comes up short for them, as well as many other common reasons, like:

• Urine color doesn't reflect lost salt that has to be replaced from sweating
• Urine color doesn't reflect over-hydration potential until it's too late
• Urine color during an evening of drinking alcohol isn't likely to tell you anything about your dehydration
• You can't always check urine color when hiking, at a public event, a long bike ride/walk, many many other scenarios
• If you are monitoring someone else (elderly, child, ect) getting them to pee on queue for you to see isn't really optimal
• If you are very actively sweating, in the heat, people can lose multiple pounds in a matter of 20 minutes, how do you check your pee color every few minutes to know when you reach a dangerous level and should stop?

Since I had to factory reset my garmin it's decided to beep every 5 miles. I use it as a reminder to take a gulp of my drink. Every 15 miles I have something to eat. Job jobbed.

Cool, can I get an electronic device to tell me when I'm hungry, when I'm tired and when I need to go to the loo...

Nah thanks.

It reminds me of when I got stopped for drink driving.

They said they were going to breathalise me, I said what's that?

"its a bag that tells you when you've had too much to drink....."

"FFS, I just married one of them!"

When I first heard it, I thought what a ludicrious product.  I sitll believe so, however, I am surprised it hit $1M!!!

I whole heartly believe my body can tell me when I am thirsty and needs a drink unlike heart rate, power, etc etc that I need monitoring to indicate to me what reading they are. 

A fool and his money...e.t.c. e.t.c so on and so forth...

I would have bought this, but the saving on the retail version is minimal if you account for shipping.  And then you still have the usual crowd funding risk.

I'll wait until it shows up in retail and order from a site that allows free shipping.

But I am interested in it, even if it is just a not very accurate toy. Checking your pee will certainly not be more accurate or convenient

Amawby is right. This is nothing more than a useless gimmick. I think they're trying to calculate dehydration by measuring changes in haematocrit. Various companies (such as Masimo) have been trying for years to produce an accurate non-invasive device to measure this and hence calculate  Hb level for use in anaesthesia & critical care, and they simply aren't accurate yet. I'd go with Yorkshire Wallet's suggestion above.

2 things about this mean that it cannot be of any use to help a cyclist (or other athlete) with hydration.

1. it uses near infrared as the sensor.  These are notoriously innacurate, espeically without an invasive (i.e. analysing a blood sample) test to baseline the system for an individual user.  Without this, they can be throw off by many, many effects - subcutaneous fat, vascularisation, skin tone, fit to the skin, ambient light...

2. by the time a hypohydration effect has occurred that this system can detect, it will be about 90 minutes too late to start drinking fluids to correct!  That is how long it takes in between drinking something and your blood plasma osmololity returning to euhydration.

The best thing you can do is remember to drink; start early and keep doing it.  If you want a gadget to help, just get a countdown timer of some sort and take a drink and set it going again each time it gets to zero.

There is a heap of medical and sports science literature out there to confirm this.

Just had an email from Knog saying that people have been recieiving wrong sizes and that people are complaining that their bells don't work or sound the way they should. They want you to take videos of the bell and you ringing it and send to them if you got a dodgy one!

They haven't even started UK ones yet - 7 months later, and that's just something relatively simple, without electronics, from a company that's already established and has cash flow.

After 2 examples of already solvent and established companies screwing up crowdfunding projects - namely  Blaze's Bunner and Knog's Oi! - I'll wait until future tech is out in retail shops and pay full price which will likely get me a unit before the backers get it and with full consumer rights if it doesn't work as described on the tin.  

I would really, really, really be dubious about the performance gain claims. As a guide I use the rule that I can lose 2% of bodyweight in water and still not have any loss in performance. 

My cheap alternative to the last picture is go to the toilet before you go out, judge the colour, have a drink.

Does it also tell you when to go to the toilet?