CISSN Topic Guide

Hydration

Hydration items test fluid replacement, electrolyte balance, dehydration and hyponatremia risk, and individualized sweat-rate monitoring.

What the exam tends to ask

Fluid needs before, during, and after training.
Electrolyte replacement and heat-illness risk management.
Why body-mass change can guide individualized rehydration.

Must-know concepts

Fluid balance

Fluid intake must be individualized because sweat rate, GI tolerance, environment, and duration vary.

Electrolytes

Electrolyte strategies matter most when sweat losses and exercise duration make plain water insufficient.

Hyponatremia

Overconsuming low-sodium fluid during long events can create a different risk than dehydration.

Practice prompts

  1. 01Calculate why post-exercise body-mass loss matters for rehydration planning.
  2. 02Explain when a glucose-electrolyte solution is more useful than water alone.