Your sweat stores a lot of information about your health
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Wow, you’re pretty salty,” says Stefan van der Fluit, looking at my numbers. I was going to tell him that. I’ve just done a sweaty 45 minute workout on the bike at the gym and the salt is already crystallizing on my shirt. But van der Fluit knows exactly how salty. I just sweated out 347 milligrams of sodium in 370 milliliters of water. That’s on the high side, sodium-wise, and I need to upgrade.
Van der Fluit is the founder of Flowbio, a London-based company specializing in sweat analysis for athletes. During training, I wore a sensor called the S1 on my upper arm, which collects sweat in a small channel, automatically measures its volume and sodium concentration, and transmits the data to a mobile phone app. Using that data, the app calculates my losses.
If I were an endurance athlete, that data would be incredibly valuable, possibly the difference between winning and losing. I don’t, but van der Fluit does. As a competitive cyclist, he has long had problems with dehydration. But since he started using the sweat sensor, they have gone away, and his performance has improved.
Flowbio’s S1 is one of the most portable sweat sensors to hit the market in recent years. They are mainly aimed at people who sweat a lot in their work – sportsmen and craftsmen – but they are available…
