YOSEMITE NATIONAL PARK, Calif. (KSEE/KGPE) — Yosemite search and rescue officials urged visitors planning to hike to Half Dome and other trails to stay hydrated while hiking in the summer heat after responding to a wave of heat-related incidents over the past couple weeks.

In one case, after successfully summited Half Dome in the early afternoon, and with only a mile or so to the trailhead, a hiker in his mid-20s was unable to continue hiking due to severe cramping in both legs.

A search and rescue team responded up the Mist Trail and wheeled the patient to the trailhead, officials said. To help with rehydration, the hiker was given an IV saline solution, which helped to improve his condition by the time they reached the trailhead.

In another case, a hiker in his 70s experienced intense muscle cramping in his legs while on the summit of Half Dome.

Bystanders descended the cables and reported his condition to the ranger checking permits at the base of the Sub Dome, officials said. By the time the ranger arrived at the top of the Half Dome cables, other hikers had given the man water mixed with electrolyte tablets and he reported that his symptoms were improving.

The ranger and the hiker descended down Sub Dome as the ranger recalled, “I had trouble keeping up with him on the way down, as he was feeling better and moving rather fast.”

Additionally, last week, in a 24-hour span, Yosemite emergency crews responded to dehydration and heat exhaustion, officials said. In all three cases, the hikers were hiking in the heat of the day. None of them were drinking adequate amounts of water while hiking.

All three reported various telltale signs and symptoms of dehydration and heat exhaustion:they felt dehydrated, fatigued and exhausted, hot and even feverish, and experienced nausea and vomiting.

The hikers went hours without urinating and when they did urinate, the urine was dark yellow.

Yosemite officials provided tips for staying strong and healthy while hiking in the summer heat:

  • Hike with—and drink—plenty of water. Eat salty snacks, or drink electrolyte beverages, to maintain a proper balance of electrolytes. Keep drinking water even after your adventure is over.
  • Pay attention to your output—if you go hours without visiting a restroom (or the woods!), your body needs more fluids.
  • Rest frequently in the shade, especially during the heat of the day. Consider soaking a bandana or buff with water and putting it around your neck to help cool your body.
  • Consider wearing sun-protective clothing and a hat to avoid sunburn and keep you cool.
  • Avoid stimulants and alcohol before, during, and immediately after a strenuous hike or other outdoor activity.
  • Half Dome: No matter how fit you are, the Half Dome hike is very strenuous. The suggested minimum amount of water intake for hiking Half Dome is 1 gallon (4 liters) per person. Equally important is ensuring you are maintaining a good electrolyte balance. Keep moving around the summit once you’ve reached the top, or if you plan to rest for a longer period, stretch before and after.