A 33-year-old runner was hospitalized for heat exhaustion and electrolyte imbalance from a light vacation workout

• Experienced runner Morgan Philpott told Insider she was hospitalized after a light run on vacation.
• High humidity may have led to heat exhaustion, according to a researcher specializing in heat illness.

A 33-year-old woman from Texas said she was treated for heat exhaustion and electrolyte imbalance after taking a short, easy run.

Morgan Philpott, a 33-year-old Texas resident, has been a runner since high school, with 5K, 10K, and half-marathon races under her belt. She routinely does three-to-five mile runs for training, and 10 to 15 mile runs once a week.

But 30 minutes of early-morning running on the beach on a recent vacation sent her to the ER, Philpott told Insider.

She said she was hospitalized with symptoms like nausea, severe headache, and confusion, which continued after she stopped exercising.

Humidity and drinking too much water without sodium likely contributed to her illness, according to an exercise science researcher specializing in heat safety.

Symptoms like severe vomiting, headache and confusion 'came out of nowhere'

It was the first day of a coastal vacation with her family when Philpot got up before dawn to go for a run, excited to get back to a workout routine after recent illness in June.

"It was the first real day of our vacation and I was still technically on the mend," she said. "I was looking forward to making a daily beach run a pleasurable way to get back on track."

Philpot ran a leisurely 15 or 20 minutes along the beach, stopping to take scenic photos, then ran back to join her family at their condo near the shore.

A few hours later, playing on the beach with her children, she developed a headache, her eyes hurt from the glare of the sun on the water, and she started to feel nauseous.

Over the next two hours, she said symptoms worsened — she was vomiting every few minutes, unable to keep down liquids, and had muscle cramps and jagged lines across her vision. Her husband drove her to the ER where she was treated with IV electrolytes and anti-nausea medication, which resolved the problem. Philpott said it took several days to feel well enough for beach activities again.

Factors like humidity and lack of electrolytes combined to make a 'perfect storm' of risk

Philpott said she's used to exercising in hotter temperatures than the 85 degree morning on the beach, but experienced a "perfect storm" of risks like prior illness, humidity and low electrolytes.

Humidity prevents the body from evaporating sweat to cool down, according to Sean Langan, an associate research director at the University of Connecticut's Korey Stringer Institute who specializes in heat injury prevention.

"Humidity impairs the efficiency of your sweat response because when you're outside in the heat, sweat evaporates the heat into the atmosphere, he said. "If you see sweat just dripping off your body, it's not doing anything to cool you down."

Combined factors of heat stress like temperature and humidity are known as the "wet bulb globe temperature."

Langan said Philpott may have experienced heat exhaustion, when the body gets too hot and is unable to cool itself effectively, causing fatigue and dizziness.

However, symptoms of heat illness can be treated by cooling the body, and don't typically persist hours later. Langan said Philpott's nausea and disorientation may have been hyponatremia, or electrolyte imbalance. Philpott had been drinking lots of water, she said, which can prevent dehydration (and further heat risk), but dilutes electrolytes.

Since her incident, Philpott said she's been adding electrolytes to her water and paying closer attention to minor symptoms like headache, in case they turn out to be warning signs of a more dangerous issue.

"I do not want to end up in the ER again. That was one of the more miserable days of my life," she said.