AU Pro Volleyball Partners with Gatorade Sports Science Institute for Hydration Testing
Athletes Unlimited Pro Volleyball athletes got a personalized look at their hydration needs when the Gatorade Sports Science Institute (GSSI) conducted sweat testing during practices on October 17 and 18 as the competition shifted to Madison, Wisconsin.
GSSI is building a female-specific dataset through the testing, which measures sweat rate, sodium loss, and fluid balance using patches worn on the arm during practice. The institute also tracked body weight, collected pre-practice urine samples, and monitored fluid intake to provide each athlete with a custom report featuring their individual sweat classification, intake habits, and personalized hydration recommendations.
The testing addresses a significant gap in sports science. Most existing hydration data comes from male athletes, and GSSI is working to build a female-specific database that will provide more accurate recommendations for women in sports.
“The Athletes Unlimited partnership is invaluable for us to learn from the highest caliber of athletes, information which will be translated to education across levels,” said Kimberly Stein, Senior Manager at the Gatorade Sports Science Institute. “Working with elite professional athletes allows us to learn from the very best in the sport and then translate those learnings to girls playing at all levels.”
For middle blocker Annyka Legros, the opportunity to contribute to female-focused research stood out.
“I was really excited to do it, knowing that a lot of studies are only done based off of male volunteers, so that limits all the science discoveries for women,” Legros said. “Some things can cross over to women, but not a lot of things work because we have a whole different anatomy.”
Understanding individual sweat patterns is crucial for optimizing performance.
“Every athlete sweats differently, mostly driven by genetics and training status,” Stein noted. “Most athletes know if they sweat ‘a lot’ or ‘a little’ but have no idea how much fluid they actually lose. What’s even harder to know is how salty their sweat is. This is important because research shows that if athletes lose more than ~2% of their body weight from sweat, performance begins to decrease.”
For professional athletes, the data provides clarity that eliminates guesswork, and setter Carly Graham jumped at the chance to learn more about her individual hydration needs.
“Our body is a huge part of our jobs, and so to make it feel its best, and doing everything you can to try and do that is really important,” Graham explained. “I think hydration is one of the biggest things. A lot of people talk about it, but they just say electrolytes, you know…But I think it’s individual for everybody and how much they sweat, or their output, depending on each day.”
The impact of proper hydration shows up in multiple aspects of performance. For outside hitter Sarah Wilhite Parsons, it’s mental as much as physical.
“For me, it’s like my focus,” she said. “My focus improves, and I can just focus on what I’m doing in the moment, versus feeling like I need to play catch-up or something like that. If you’re on top of it, you don’t have to always think about it.”
Graham notices the difference in how her body feels and responds during competition.
“I feel way more fluid. When I’m dehydrated, I feel like my muscles get really locked up on me. I cramp very, very easily,” Graham said. “I’ve known that my whole life…I notice the biggest difference when I’m hydrated.”
This marks the second collaboration between Athletes Unlimited and GSSI, following sweat testing conducted during the inaugural season of the Athletes Unlimited Softball League this summer.
The GSSI has conducted research with athletes for over 40 years, studying the effects of exercise, environment, and nutrition on the human body. The data collected from AU Pro Volleyball athletes will contribute to GSSI’s growing database of female athlete research and help develop educational resources for women in sports at all levels.
Siera Jones is the digital media reporter at Athletes Unlimited. You can follow her on Instagram and X @sieraajones.
