Former Alaska Gov. Sarah Palin bewildered even ardent runners recently when she said on Facebook that she gashed her head while "rock-running."
"What's rock running? No clue, but Sarah Palin says that's what she was doing when she fell and opened a bloody gash on her forehead," wrote Amy Graff for SFGate, the website of the San Francisco Chronicle.
On Mediaite, J.D. Durkin wrote about Palin's injury, explaining that Palin was "engaging in something called 'rock running,' a sport (I guess)."
The internet isn't much help. Google "rock-running" and you'll find rock songs to listen to while running, information about a race called The Rock Run on Nantucket Island, and a YouTube video showing a bikini-clad woman carrying a rock while running under water.
Assuming that wasn't Palin, we're left to presume the former Republican vice presidential candidate, a mother of five who is famously athletic, was purposefully running across rocks when she fell. Spartan Race participants sometimes carry rocks, and trail runners traverse boulders and pebbles, so this isn't as strange as it seems.
Nonetheless, Palin might want to change out a vowel and try another form of running that's gaining popularity: ruck-running.
This is a military-type exercise that involves running while carrying a backpack, also known as a rucksack.
Ruck-running, or rucking, is "the fitness trend men everywhere can't get enough of," according to Men's Fitness magazine, which promised last year that runners could "shed fat, ditch back pain, and be a beast in the gym" if they'd just strap on a weighted backpack.
There are even rucking competitions, called GORUCK events, led by members of the military's Special Forces.
Writing about participating in one, Christine Van Dusen said some people like rucking because they identify with the military; others see it as a form of rebellion against boilerplate life. "Me, I just like to feel strong, and to see what my body can do," she wrote for Atlanta magazine in June. (Note to Palin: There are also rucking events in Alaska.)
The website Breaking Muscle advises would-be ruckers to start light, with maybe a 10-pound load, and to build slowly, adding no more than 10 percent more weight each week. "And take time after every session to stretch out, particularly the back and shoulders, as you will stiffen up quickly otherwise," Australian fitness coach Andrew Read wrote.
Of course, not everyone believes that carrying a heavy backpack is good for the body, particularly parents of school-aged children. As Max Plenke memorably wrote last year for Mic.com, many kids lug around backpacks that weigh 40 or 60 pounds, which can be "the equivalent of walking around all day with a golden retriever hanging from your shoulders."
The American Academy of Pediatrics recommends that children carry no more than 20 percent of their body weight, and also to always use both straps, not one, which can cause muscle strain.
That's good advice for ruckers, too — whether or not running over rocks.
EMAIL: Jgraham@deseretnews.com
TWITTER: @grahamtoday