You probably heard this biological factoid in fifth grade health class: two-thirds of the human body is made of water. What you probably weren’t told, though, is just how drastically water could impact your morning, daily, and nightly routine. Your physical fitness depends on hydration, as does the quality of your sleep. Even the clarity of your thoughts and the stability of your moods are affected, in part, by your body’s water content at any given moment.
But measuring your body’s hydration is no cakewalk. “Smart” water bottles can tell you how many ounces of liquid you’ve consumed in the course of a few hours, but not how much your body has actually absorbed — that level of granularity usually requires a trip to a medical lab or emergency room. But that’s poised to change. Recently, health startup BSX Technologies debuted the LVL, a wearable that promises to measure hydration in real time.
It’s the first of its kind, BSX Technologies Chief Executive Officer Dr. Dustin Freckleton explained in a phone interview with Digital Trends. Most fitness trackers on the market rely on phyotoplethysmography (PPG) to measure everyday vitals like heart rate and blood oxygen level — basically, tiny sensors that emit green light toward and through the upper layers of your skin. Because blood is red and absorbs green light, they’re able to roughly gauge flow through your veins. Between heart beats, there’s less absorption of green light, and during heart beats, there’s more.
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The LVL, by contrast, packs an infrared sensor that penetrates far beneath the surface of the skin — up to ten times as deep compared to sort of green light sensors found in, say, the new Apple Watch or latest Fitbit. That depth allows the LVL to capture spectroscopic images — what Freckleton calls “direct measurements” — of blood from which it can derive the percentage of water content and heart rate. Perhaps more importantly, though, infrared lets it do so more accurately than your average wearable. While most trackers deviate anywhere between 14 to 40 beats per minute from your actual heart rate, the LVL’s measurements are accurate to within 3.
The impetus for the LVL was a traumatic experience Freckleton had in medical school. As a physician in training, he hit the books hard — sometimes studying for as many as 16 to 18 hours without rest. His mental toil began to take a toll: one day, Freckleton awoke with a pounding headache. “I was in the bathroom, staring at myself in my bathroom’s vanity mirror,” he said, when he noticed something alarming: he’d begun standing inexplicably crookedly. Then, the unthinkable happened. “I righted myself, looked back at the mirror, and the strength began draining out of my body.” In 45 seconds, Freckleton was completely paralyzed on his left side.
He was rushed to the emergency room. Physicians gave him the sobering diagnosis: a stroke. He was a 24. “I exercised regularly and had no preexisting conditions to speak of,” he said. “It was a shock.” Acute dehydration was pegged as the underlying cause, a diagnosis that Freckleton took to heart. “It pivoted the focus of my entire career,” he said.
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Freckleton sought an easy, reliable method of measuring the water content in blood, but found most consumer products weren’t up to the task. “The technologies weren’t able to measure hydration in real time,” he said. “There weren’t any commercially available solutions that could’ve prevented my situation.” And so he bootstrapped, recruiting a team of engineers and medical practitioners to develop a solution of his own: a “smart band” that could measure hydration on the fly.
Freckleton embarked on an intensive cycle of research and development, recruiting “hundreds” of test subjects over a five-year period to run gauntlets in what Freckleton called the “Sweat Lab”: a super-hot, low-moisture environment designed to purposefully dehydrate. They provided the baseline for LVL’s algorithms. Today, hydration levels are within 0.32 off actual values measured in the lab, a level of accuracy which he said exceeds military and first-responder standards.
It’s frighteningly easy to become dehydrated. “We’ve evolved as human beings, but we haven’t accounted for those changes in our habits. It used to be that we consumed food and water all day, but now we’re not drinking nearly enough.” Most people become dehydrated when they least expect it, he said — like when they’re sleeping. “You’re passively dehydrating for eight hours. You wake up feeling crappy, and it’s usually because you’re clinically dehydrated.”
And that’s where Freckleton’s wearable the LVL and its companion app come in.
The LVL is a simple wearable band with a full-color touchscreen, physical buttons, a Bluetooth antenna, an accelerometer, and a battery that lasts four hours on a charge. The little display sits in a leather or silicon band, which has a simple clasp. It looks a lot like the Misfit Ray or a Fitbit.
The LVL syncs up to a companion app on your phone, which packs algorithms that learn your habits over time. As the band learns, the LVL will re-calibrate accordingly. It might instruct you to drink six ounces of water before a workout, or 12 ounces before you hit the hay for the evening. It’s predictive, too. The wearable can project how well you’ll perform at, say, basketball in several hours based on how much water you’ve consumed.
The goal isn’t just to expose data points like hydration level and heart rate, Freckleton said, but to extract actionable insights from it. “Hydration alone is an interesting metric, but more interesting is how it’s affecting you on a daily basis.” In that sense, LVL’s real value is its perspicacity.
“With a single tap, you can see how you’re feeling,” Freckleton said. “It can show you how much better you feel when you’re hydrated, and show you how to do better.”
It’s a neat idea that we’ve never seen before, and we’ll be interested to see how well it does with the crowdfunding campaign. The LVL recently launched on Kickstarter for $200. If you’re interested, you can back the project on Kickstarter right now.