Summer is Officially Here! Let's Chat Hydration & Heat Acclimatization
The first official weekend of Summer is here, and with it comes one of my favorite topics to nerd out on with fellow sports dietitians: how do we actually prepare our athletes for the heat — and how do we make hydration something they buy into and get excited about! I'm still thinking about the insights shared at our ASPDA Annual Convention in New Orleans last month, where Dr. Neil Walsh and Dr. Louise Burke both brought the science to life. What the Science Is Telling Us Dr. Walsh's work on heat acclimation is a great reminder that we don't need to send athletes to a sauna or a hot climate to get adaptations. Research from his group has demonstrated that post-exercise hot water immersion on six consecutive days in temperate conditions can elicit meaningful heat acclimation adaptations — including earlier onset of sweating, reduced resting and exercising core body temperature, and reductions in cardiovascular strain. A practical, low-barrier protocol that many of us can implement with our teams right now . Post-exercise Hot Water Immersion Elicits Heat Acclimation Adaptations That Are Retained for at Least Two Weeks On the physiology side, the GSSI reminds us why this matters: heat acclimatization creates biological adaptations that reduce physiological strain, improve comfort, improve exercise capacity, and reduce the risks of serious heat illness during heat stress. Heat Acclimatization to Improve Athletic Performance in Warm-Hot Environments Dr. Burke has long championed the importance of individualized hydration strategies, and GSSI echoes this well: the success of any hydration strategy will depend on the context of the event — duration, intensity, and environment — as well as the characteristics of the individual, including fitness and acclimatization status. https://www.gssiweb.org/en/sports-science-exchange/Article/fluid-intake-strategies-for-optimal-hydration-and-performance-planned-drinking-vs.-drinking-to-thirst Hydration in the Heat: Key Reminders for Practice A few evidence-based points worth emphasizing to your athletes: During intense or long-duration exercise in warm-to-hot conditions, sweat rates can easily top 1 liter per hour . Relying on thirst alone often isn't enough to keep up — a phenomenon called voluntary dehydration — and once a body water deficit passes 2% of body mass, performance starts to take a hit. Athletes who notice white salt stains on clothes or skin may need more sodium during exercise and throughout recovery. A hydration plan removes the guesswork, especially during longer or more intense training sessions. A great plan helps athletes stay ahead of sweat loss and feel better when they're performing. Would love to continue to chat below on exactly how we all are putting these plans together for our athletes! Athlete Hydration 101: A Complete Science & Strategy Guide The GSSI's research also highlights that what's inside the drink matters — from thirst triggers to fluid retention, every ingredient plays a role. https://www.gatorade.com/resources/hydration-science-for-athletes-fluids-electrolytes-recovery Bringing Hydration to Life in Practice This is where I think sports dietitians and athletic trainers have such an edge — we can make hydration fun and memorable for athletes. A few ideas that have worked well (and would love to hear yours!): Sweat rate testing stations during preseason — athletes love seeing their own data, and it's a great anchor for personalized fluid targets Urine color check-ins using the classic hydration chart posted in locker rooms (low-tech, high impact) Summer hydration stations stocked with infused waters, juice and electrolyte mocktails, or even Gatorade Slushies! Pre/post weight checks during hot/high intensity sessions to show athletes how much fluid they're losing and how much they need to drink to get back to baseline Let's Chat What heat acclimation strategies are you implementing this summer? Are you using hot water immersion, sauna protocols, or heat training blocks? And what's your go-to move for making hydration engaging? Drop your questions, tips, beverage recipes, and experiences below. The GSSI library at gssiweb.org is also a fantastic resource if you want to dive deeper into the literature!