What are common signs of dehydration on a hike?

• A. Thirst, dry mouth, dark urine, fatigue, dizziness.
• B. Heavy sweating with clear urine.
• C. Frequent urination at night only.
• D. Rash with fever.

Answer: (A)

Recognizing dehydration on a hike comes from noticing how your body signals fluid loss during activity. Thirst and dry mouth appear as your body tries to prompt you to drink, while dark urine shows the kidneys conserving water when you’re not taking in enough fluids. Fatigue and dizziness happen because reduced circulating fluid lowers blood volume, which means less oxygen and nutrients reach your muscles and brain during exertion. These signs fit dehydration because they come from the body's need to preserve water while you’re losing it through sweat.

Heavy sweating with clear urine isn’t a sign of dehydration; clear urine usually means good hydration, or that you’ve recently replaced fluids. Frequent urination at night isn’t related to hiking dehydration, and a rash with fever points to another illness or infection rather than fluid loss.

If you notice dehydration signs, pause, rest in shade, and sip small amounts of water or an electrolyte drink. Monitor how you feel, and seek medical help if symptoms worsen, or if you can’t keep fluids down, you become confused, or you faint.