Professional sweat testing with the Nix Pro biosensor. We measure how much you sweat and how much sodium you lose, then build a detailed hydration plan around your own numbers, not generic recommendations.
Book Your Sweat TestYour sodium losses are as unique as your fingerprint. One-size-fits-all hydration plans fail because they ignore the data that matters.
Sweat sodium concentration ranges from 200 to 2,000+ mg/L person to person. Two athletes training side by side can have 10x different sodium losses. You cannot guess this number.
As little as 2% body mass loss from dehydration measurably reduces power output, cognitive function, and endurance capacity. Knowing your sweat rate lets you prevent it precisely.
Under-replacing sodium leads to muscle cramping and fatigue. Over-drinking without sodium replacement risks hyponatremia, a potentially dangerous drop in blood sodium. Both are preventable with data.
Sweat volume and sweat concentration: the two numbers that turn your hydration strategy from guesswork into a plan.
Measured in L/hr: how much fluid your body loses during exercise. This determines how much you need to drink. It changes with intensity, temperature, and humidity, which is why testing under different conditions gives you a more complete hydration profile.
Measured in mg/L: how much sodium you lose in every liter of sweat. This determines what you need to replace. Combined with your sweat rate, it gives your sodium loss per hour, the number your fueling plan is built on.
One session at our facility, results the same day. No samples to mail, no waiting on a lab.
Schedule your sweat test online. We send preparation instructions before your visit, including guidelines on hydration and food leading into the session.
We prep the skin and apply a single-use Nix sweat patch to your arm, with the Nix pod clipped on. No finger pricks, no blood draws.
You complete a controlled session at our facility, bike or treadmill, at the intensity you want answers for. Once you are sweating steadily, the sensor reads your sweat continuously.
Your session data is processed on the Nix Pro platform: sweat volume, sweat sodium concentration, and sodium loss per hour.
We walk you through your numbers and build a detailed hydration plan: how much to drink and how much sodium to take per hour, for training and for race day.
Professional Nix Pro sweat analysis with a detailed hydration plan included.
One sweat test session
Nix Pro sweat volume and sodium analysis
Results the same day
Detailed hydration plan
Two sweat test sessions
Test different disciplines (bike vs. run)
OR different conditions (heat, intensity)
Hydration plan for both
Save $50 vs. two singles
Bundle discounts do not apply to sweat testing. Both options include the Nix Pro analysis and your hydration plan.
If you train hard, race long, or suffer in the heat, this test gives you answers.
Dial in fluid and sodium for efforts lasting hours
Test both bike and run to build a multi-discipline plan
Training in heat amplifies sweat losses; know your numbers before summer
Chronic cramping during events often points to a sodium deficit. Test and find out.
When nutrition falls apart late in a race, hydration strategy is often the root cause
You already track power, HR, and VO2. Add the hydration variable to your stack.
Stop relying on general guidelines. Get your sweat volume and sodium concentration measured, then follow a plan that is yours, built on your own numbers rather than trial and error.
Book Single Test · $125 Book Double Test · $200