3 Things Every Coach
Gets Wrong About Heat Practices
The temperature hits 95 degrees and the humidity is climbing. You've got a two-hour practice scheduled, a field full of kids, and a cooler of water bottles sitting at the sideline. You're covered, right? Maybe not.
As a track coach and someone who has spent years studying what actually keeps athletes performing safely in the heat, I've watched well-meaning coaches make the same three mistakes over and over. None of them are about not caring. They're about not knowing what the research actually says — and there's a meaningful gap between what most coaches do and what the science recommends.
Here's what's getting missed, and more importantly, what to do instead.
Treating Water Breaks as the Whole Strategy
Water breaks are necessary. But they are not sufficient — and confusing the two is where things go wrong.
Most coaches call water breaks when there's a natural pause in practice: between drills, at halftime, when they remember. The problem is that by the time you remember, athletes have often already crossed into early dehydration. Research is clear that a loss of just 1–2% of body weight through sweat is enough to elevate heart rate, impair cognitive awareness, reduce anaerobic power, and increase perceived exertion — all before an athlete feels noticeably thirsty.1
Thirst is a late signal. It's the body's backup alarm, not its first warning.
The fix isn't more water breaks — it's scheduled water breaks, built into the practice plan before you step on the field. The National Athletic Trainers' Association recommends fluid replacement every 15–20 minutes during exercise in warm conditions, not when convenient.2 That means designing your practice around the breaks, not the other way around.
In extreme heat (heat index above 90°F), that interval drops to every 10–15 minutes. And in those conditions, water alone often isn't enough — which brings us to the second mistake.
Giving Athletes Water When They Need Electrolytes
Water rehydrates. Electrolytes keep the body's systems functioning. In practice lasting longer than 60 minutes — or any practice in significant heat — athletes need both, and coaches who hand out plain water are solving only half the problem.
Here's why it matters: sodium and chloride are the two electrolytes lost in the largest quantities through sweat, and the variation between individual athletes is enormous. Research has found sodium loss in athletes ranging from as low as 160mg per liter of sweat to over 2,200mg per liter — meaning one athlete on your roster might be losing ten times more sodium than the athlete standing next to them.3
Sodium isn't just about cramps. It's the most abundant ion in extracellular fluid, plays a critical role in nerve-to-muscle signaling, and directly affects the body's ability to absorb nutrients into cells. When sodium drops, performance and focus drop with it.
For sessions under 60 minutes in mild conditions, water is generally adequate. But for longer sessions, hot-weather practices, or back-to-back training days, athletes need a beverage that replaces what sweat actually takes away: sodium, potassium, and magnesium alongside fluids. This is exactly why Acuity Sport was formulated the way it was — optimized electrolytes, no caffeine, clean ingredients designed by a coach who also happens to be a parent.
The Johns Hopkins Sports Medicine team puts it simply: "The longer you exercise, the more important it becomes to replace electrolytes, not just fluids."4
Skipping Heat Acclimatization at the Start of the Season
This one is the most dangerous mistake, and it's almost universal.
Preseason practice starts. It's hot. You run a full-intensity session. An athlete goes down.
What most coaches don't realize is that the first 7–14 days of outdoor training in warm weather represent the highest-risk window of the entire season. The body's heat adaptation mechanisms — increased plasma volume, earlier onset of sweating, lower sweat sodium concentration — take time to develop. Throwing athletes into full-intensity practice before that window has passed puts them at real risk.
The NATA's preseason heat-acclimatization guidelines are explicit: the heat-acclimatization period should cover the first 14 consecutive days of preseason practice, with intensity and duration ramped up gradually rather than starting at full load.5 The Korey Stringer Institute at the University of Connecticut, one of the leading research centers on exertional heat illness, identifies acclimatization as one of the most effective interventions available for reducing heat stroke risk.6
Exertional heat stroke is the leading cause of preventable, non-traumatic sudden death in young athletes in the United States. The NATA's position statement notes it is 100% survivable if recognized and treated immediately — which means the tragedy is not in the condition itself, but in the preparation that didn't happen beforehand.
Two weeks of progressive intensity at the start of the season isn't a luxury. It's the baseline.
What Actually Keeps Athletes Safe
The full picture looks like this: scheduled breaks (not reactive ones), the right fluids for the duration and conditions, and a preseason ramp-up that respects the body's acclimatization timeline. None of it is complicated. All of it requires intention.
Youth athletes are not small adults. They sweat less efficiently, heat up faster due to their higher body-surface-area-to-mass ratio, and are significantly less likely to self-report symptoms.7 The burden of protection falls on the coach.
Water breaks are a start. Build the rest of the system around them.
Safety in the heat isn't one big decision — it's a system of small ones. Schedule the breaks, match the drink to the conditions, and ramp the first two weeks. Do those three things and you've already separated your program from most of the field.
- Human Kinetics — Electrolyte Losses and Replacement During Exercise
- National Athletic Trainers' Association — Fluid Replacement for the Physically Active Position Statement
- STYRKR — How Much Sodium Do You Lose in Sweat?
- Johns Hopkins Medicine — Sports and Hydration for Athletes
- National Athletic Trainers' Association — Preseason Heat-Acclimatization Guidelines for Secondary School Athletics
- Korey Stringer Institute, University of Connecticut — Heat Acclimatization
- U.S. EPA — Heat and Teenage Athletes
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