On busy weekends in spring or fall, greater than a thousand folks will set off from one in all 3 key trailheads to hike the Grand Canyon from rim to rim—a quantity that has been climbing steadily for years. They’ll cowl a complete of 21 to 23.5 miles, relying on the route they select, dropping some 6,000 ft to the canyon flooring, the place temperatures continuously exceed 100 levels and generally hit 120, then climbing again out. On peak weekends, so many rim-to-rim hikers will name for assist that each paramedic ranger within the nationwide park must be known as into motion.
For that purpose, the park’s Preventive Search and Rescue group has been attempting get a greater deal with on who undertakes R2R crossings and what their typical conduct patterns and physiological responses are. A new study within the journal Wilderness & Environmental Medicine, by researchers on the University of New Mexico working with park employees, provides some information that shall be helpful for anybody who’s considering doing the hike.
On 2 weekends in May and October 2015, usually the busiest months, the researchers frolicked at 3 trailheads (the South Kaibab and Bright Angel trails on the South Rim, and the North Kaibab path on the North Rim), in addition to the halfway level at Phantom Ranch on the canyon backside. A complete of 617 hikers crammed out types giving info on their preparation, demographics, fatigue ranges, and different elements. Here are some highlights from the info.
The hikers had a mean age of 43, had been 65 % male, and (maybe surprisingly) had a imply BMI of 25.3, proper on the border of chubby. Lots of them had prior expertise: 40 % of them had finished the R2R hike earlier than, and 33 % had finished it no less than 5 instances. One individual reported 46 earlier crossings.
The median time taken to cross the canyon was 11.9 hours, with most individuals beginning round dawn (common time 5:30 a.m.) and ending simply earlier than sundown (common time 5:30 p.m.). You can get a way of the vary of beginning and ending instances from this graph:
Interestingly, that median time was similar for northbound and southbound hikers, regardless that the north trailhead is about 1,000 ft greater than the south trailheads. The cut up instances, nonetheless, had been fairly completely different. Southbound hikers took 5.8 hours to go down, then 6.1 hours to go up; northbound hikes zipped down in 4.3 hours, however then needed to slog upward for 7.6 hours. Neither descending nor ascending for hours on finish is simple on the physique, so it’s not apparent which is tougher. Pick your poison.
There’s fairly a bit of research of hydration methods. About half of the hikers used each a bottle and bladder, whereas 20 % used bottle solely and 31 % used bladder solely. The researchers aren’t followers of the latter method: “We consider the singular use of hydration bladders in the desert to be high risk because the tough and spiny desert environment has ample opportunity to pierce the sides of a hydration bladder.”
Overall, the hikers drank a mean of three.3 liters (112 ounces) of fluid, however there was fairly a variety. 1 / 4 of respondents drank lower than 1.1 liters, whereas 1 / 4 drank greater than 5.1 liters. Interestingly, girls drank at a comparatively constant charge no matter how lengthy they took to finish the hike, averaging 5.5 milliliters of water per kilogram of body weight per hour. Men, however, didn’t essentially drink extra in the event that they had been on the market for longer.
That distinction exhibits up within the graph beneath, the place the speed of fluid consumption for ladies is a comparatively straight line as a perform of whole crossing time, whereas for males it’s a line sloping downward:
This graph additionally exhibits that the quickest hiker within the examine took simply over six hours. (For comparability, ultrarunner Taylor Nowlin just lately ran R2R2R—that’s, all the way in which throughout the canyon and again—in a brand new women’s fastest known time of seven hours, 25 minutes, and 58 seconds. The men’s record of 5:55:20 is held by Jim Walmsley.) And it additionally exhibits that a number of folks, all males, appear to have drunk subsequent to nothing for the complete hike, even when they had been on the market for 18 hours. You type of have to wonder if these guys understood the query or knew the scale of their water bottle.
Finally, how onerous is that this hike? On a scale of 1 to 10, the median stage of self-reported fatigue was 7, which corresponds to “strong fatigue.” But there have been some nuances. Here’s how the degrees of fatigue on the finish of the hike panned out relying on how well-prepared the hikers reported being:
It’s tiring for just about everybody. But not surprisingly, it’s most tiring (as indicated by the larger bars on the right-hand aspect) for many who had been the least ready. So if you happen to’re going to hike R2R within the Grand Canyon, do your self—and the poor overworked rangers—a favor by getting match, planning nicely, and wrapping your hydration bladder in a cactus-proof protecting coating.
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