Mail-in sweat test · single conditionThe Test Kit
One lab-grade test of the sweat you lose in a real effort — turned into the sodium number you fuel against, and a race-day plan you can follow.
$129.00vs $175.00 for an in-person lab test
Free standard shipping. One test, complete results. Usable result, or your money back.
Science shown, not hidden What you get backThe one number that drives every fueling decision.
Sodium loss rate, sweat rate, and total loss — always tied to the effort they were measured in, never a naked figure.
What you get backLab-grade
Sodium loss rate
1,320mg Na/hr
measured during a long, hot training effort
How it works01
Order your kit
It ships free and arrives in a few days.
02
Collect during a real workout
Wear the pads through the conditions you actually train in.
03
Mail it back
Seal the bag, drop it in any mailbox. Postage is prepaid.
04
Get your number
Your sodium loss rate plus an hour-by-hour race-day plan.
The science, shown not hidden→
Whole-body corrected
1,100mg/L
We show both numbers and the equation we used. Whole-body = regional × 0.59 (Baker et al. 2018). No black-box number.
In the box2 forearm collection pads
Medical-grade adhesive + absorbent pad, one per arm
QR-coded collection bag
Links the kit to your account in one scan
Prepaid return label
Drop it in any mailbox — we cover the postage
Step-by-step instruction card
The weigh-in protocol that makes the numbers real
No house electrolyte. Ever.We tell you what to replace — then point you at whatever you can actually get.
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