The Ideal Candidate for a Precision Hydration Sweat Test

By Guest Blogger | 2 Minute Read

After running this sweat test for hundreds of clients over the past 3+ years, I can boldly state that EVERY active individual is the perfect candidate for this test. I’ve tested triathletes, runners, ultra runners, cyclists, swimmers, hikers, tennis players, hockey players, mixed martial arts athletes, motorcycle racers, and simply active people.

No one is immune to sweating, and the potential negative effects of sodium losses that can’t be replaced quickly enough. Especially in the unforgiving climate of Scottsdale, Arizona, where I live, train and work.

The summers here (June through September) are brutally hot, and the surrounding months of May and October are usually not too cool. Which translates to 100+ degree of hot (and sometimes humid) weather for half of the year. Athletes here must be one step ahead with their hydration replenishment, or things go downhill quickly.

Whether your sweat rate is heavy or light, whether your sweat composition is salty or not, you STILL need to understand what you are losing and how to appropriately replace it! This test isn’t just for the heavy, salty sweaters that cramp at the drop of a dime, although I’ve sure seen my fair share of this type of athlete. It’s for all athletes who lose sodium through their sweat. No one is exempt.

Many of the athletes I test feel that they are doing an adequate job replacing of fluid and sodium, and guess what? Most aren’t even coming close to what they need. For example, averaging 300 milligrams per hour over a 6-hour Ironman bike instead of 800 milligrams per hour. Huge difference here! Oftentimes, the athlete doesn’t even realize they are sodium depleted after a long training session or bike. They aren’t cramping after all.


Sweat Test machine


But cramping is just one of the indicators of hyponatremia. Other less-obviously-attributed-to-hydration imbalance symptoms are gastrointestinal issues, fatigue and lack of recovery.  Definitely not things you want to mess around with! 

In a world where we are inundated with salty foods, sometimes clients are hesitant to implement the necessary sodium protocol. Understandable. After all, you’ve lived your whole life being taught to consume moderate amounts of sodium. But keep in mind that the active athlete is sweating and therefore losing fluids and electrolytes (mainly sodium) and this must be replaced.

So here I am - making a shameless plug for this test that I believe in so much. Stop guessing, and zero in on exactly what your sodium losses and needs are. Find a sweat tester in your area, and get booked NOW... before summer really hits. You won’t regret it one bit!

Brooke Schohl, MS, RD, CSSD is a Registered Sports Dietitian and the Owner/Founder of Fuel to the Finish Endurance Nutrition Coaching in Scottsdale, Arizona.  Brooke has been racing triathlons for over a decade and truly understands the demands that endurance sports place on the body.  She’s a 4-time Ironman, her most recent one being the Xtreme Triathlon, Norseman.  She’s passionate about helping her clients develop simple, effective fuel plans that lead to the accomplishment of big goals.  For more information on services, visit

Was this article useful?

Share this article

Get your free personalized hydration plan

Take the sweat test