Section A · The Box & The Floor
HYROX
Eight runs, eight stations, and a sodium bill nobody budgets for.
Sixty to a hundred minutes of sustained effort in a warm hall. The runs punish anything sugary in the stomach, so most people drink nothing, and the farmer’s carry collects the debt.
You cannot out-run a sodium deficit. By the wall balls it has already decided your time. Two per race, both before the gun. Three on doubles or relay days. One a day in training week. One stick in 16 oz covers a window; the schedule below covers the day.
A heavy sweater’s race: the book’s 1,400 mg of sodium out, spread evenly over the eight legs, against 600 mg a stick. It is a ledger, not a blood test, but it shows the shape. Water alone ends the race 1,400 mg short, and the last three stations run on the deepest part of that hole. A typical sweater loses half as much and finishes ahead on the same two sticks.
The numbers behind HYROX
Sixty to a hundred minutes of sustained effort in a warm hall. The runs punish anything sugary in the stomach, so most people drink nothing, and the farmer’s carry collects the debt.
Why this happens
Sweat is more than water. Every ounce takes sodium with it, and sodium helps your blood hold its volume. Lose enough, and there is less blood to carry oxygen to your muscles. Your heart rate climbs at the same pace. You run hotter. The signal that tells a muscle to relax gets noisy. The cramp, the dizzy feeling when you stand up, and the pace you cannot hold all come from that one cause.
Plain water puts the fluid back, but not the sodium. That is why water alone can feel like it is not working. The fix is to put back what left: water and the minerals that went with it, in about the same mix you lost.
HYROX is about five miles of running broken up by eight stations, in a hall that is warm before the first wave starts. Sweat runs from the gun. Most people drink nothing during the race because the runs punish anything sitting in the stomach, so the sodium that leaves in the first half never comes back. Nothing feels wrong through the ski and the sleds. Then the farmer’s carry arrives, the forearms and calves cramp, the lunges lock the hamstrings, and the wall balls turn into a survival exercise.
You cannot out-run a sodium deficit. By the wall balls it has already decided your time.
Forty to seventy ounces out, and the 2% line lands on the lunges
Eight runs and eight stations in a warm hall take 40 to 70 oz of sweat. For a 175-lb athlete the 2% line sits at 56 oz. The heavy end crosses it just after the farmer’s carry, which is why the lunges and the wall balls are where races fall apart.
A HYROX of about 90 minutes is 40 to 70 oz out. A heavy sweater passes 2% (3.5 lb, 56 oz for a 175-lb athlete) early in the last quarter, right as the lunges start. Everyone else finishes two to three pounds down.
The book’s 40 to 70 oz a race, split evenly across the eight legs, in the order of the official race format. A heavy sweater crosses 2% (56 oz for a 175-lb athlete) on leg seven, the sandbag lunges, and the book puts the cramps at six and seven. A typical sweater finishes the race short of the line.
One stick with breakfast and one at T-90 is 1,200 mg in before the gun, which covers most of the range. A heavy sweater in a hot hall runs past it, and so does a doubles or relay day, which is where the book adds the third stick.
What you get back when the sodium goes in before the gun
Pooled across 28 studies, being dehydrated cost 8.3% of muscle endurance. Runs five to eight are endurance work on legs the sleds already used.
Savoie et al., Sports Medicine, 2015The same analysis put the loss in anaerobic power at 5.8%. Wall balls are 100 reps of it, and they come last.
Savoie et al., Sports Medicine, 2015At about 1.5% of body mass down, a controlled trial found more errors on attention and memory tasks, with more fatigue. The call to push or hold on run six gets made in that state.
Ganio et al., British Journal of Nutrition, 2011Drinking more than you lost only rehydrates you when the drink carries enough sodium. Below that, the extra leaves as urine, which matters on a doubles or relay day.
Shirreffs et al., Med Sci Sports Exerc, 1996Chugging water at the line sloshes on run two. A sugary drink upsets your stomach on every run after it. Nobody drinks on the course, so the book puts both sticks in before the gun: one with breakfast, one at T-90, then a few sips of plain water in the last 20 minutes.
The Hydration Playbook
Dry, then hydrated, piece by piece
The red panel is what is happening now. The green one is what the next section buys you, and roughly how long each part takes to show up.
- Heart rate high from the gun, sweat pouring in a warm hall
- Plain water at the start line sloshes on run two
- Sodium loss is already 300+ mg and you have not noticed
- Blood volume drops; the same pace costs more heartbeats
- Forearms and grip start to go on the row
- Focus narrows; pacing decisions get worse
- Farmer’s carry cramps in the forearms and calves
- Lunges lock the hamstrings
- Wall balls become a survival exercise
What to drink, and when
Start with morning. It is the window most people in HYROX get wrong. For a normal training day rather than a race, the timing guide covers every window.
MORNING
- Stick 1 in 16 oz with breakfast
- 60–80 g of carbs: rice, oats, bananas
Starts the sodium top-up hours before the gun, while your stomach has time to settle.
T-90
- 16–20 oz with stick 2 at T-90
- 8 oz plain water in the last 20 min
Both sticks are in before the gun, so nothing has to go down on the course.
AFTER
- 24 oz per pound lost
- Salty food, then a real meal
Restores blood volume before the next heat, or before the drive home.
The book’s HYROX number: every pound lost is 24 oz to put back, with electrolytes in it. Weigh in before a full sim and out after, and you know your own race-day bill.
What to take, and what we do not sell
Two of these three are things we do not sell. A hydration stick does not fix fuelling, and pretending otherwise is how people end up disappointed.
Electrolytes
Fuel
Worth taking too
The questions we get about HYROX
How much do you sweat in HYROX?
40–70 oz of sweat over a full HYROX. 700–1,400 mg of sodium gone by the finish line. Weigh in before and out after a session: every pound down is about 24 oz you did not put back.
When should I drink during HYROX?
Breakfast, three hours out: Stick 1 in 16 oz with breakfast; 60–80 g of carbs: rice, oats, bananas. Starts the sodium top-up hours before the gun, while your stomach has time to settle.
What should I drink before HYROX?
Breakfast, three hours out: Stick 1 in 16 oz with breakfast; 60–80 g of carbs: rice, oats, bananas. Starts the sodium top-up hours before the gun, while your stomach has time to settle.
How do I recover after HYROX?
The first hour after the finish: 24 oz per pound lost; Salty food, then a real meal. Restores blood volume before the next heat, or before the drive home.
Do I need electrolytes or is water enough?
Water puts back the fluid you sweat out. It does not put back the sodium, potassium and magnesium that left with it, and without sodium your body cannot hold on to the water. Per hour of hard work: Sodium 500–700 mg, Potassium 150–300 mg, Magnesium 30–60 mg, Water 16–24 oz.
How many sticks do I need?
Two per race, both before the gun. Three on doubles or relay days. One a day in training week. Nobody drinks on the course. Rehearse race morning in your sims: stick 1 with breakfast, stick 2 at T-90, then a few sips of plain water. The starter kit has 40 sticks in five flavors.
Should I eat or drink during HYROX?
No. Nobody drinks on the course, and the runs punish anything sitting in your stomach. Get it all in before: 2 g of carbs per pound of body weight the day before, 60 to 80 g at breakfast three hours out, a stick with breakfast and a second stick at T-90.
Why do I cramp on the farmer’s carry and the lunges?
By station six, you have sweated out a lot, and none of it comes back, because nobody drinks on the course. The carry works your forearms and calves. The lunges work your hamstrings. Both hit when your sodium is at its lowest. The book’s fix is to start topped up: one stick with breakfast and a second at T-90. Plain water on its own makes the cramp more likely. Here is why you cramp even when you drink water.
Do I need more electrolytes for HYROX doubles or relay?
Yes. The book says two sticks for a single race and three on a doubles or relay day, with the third after the finish or between heats. After the race, put back 24 oz for every pound you lost, then eat something salty and a real meal.
How should I hydrate for HYROX training?
Take one stick a day in training weeks. Rehearse race morning in your sims: a stick with breakfast, a second at T-90, then a few sips of plain water. The stations train the way they race. The CrossFit guide covers sleds and wall balls in a WOD. The rowing guide covers the erg. The timing guide covers a normal training day.
Everything in the box
The book this article came from is in there too. One page for every sport, so the next thing you take up is already covered.
Five flavors, one stick each
Taste is the one thing you have to try for yourself. The starter kit gives you all five, so you find the one you will actually reach for.
- All five minerals sweat costs you, no sugar. See the label.
- Informed Sport certified, batch by batch.
- Mixes into whatever bottle is already in the kit bag by the start pen.
