The Mystery of the Pro Runner and the Electric Shock

It was supposed to be a routine tune-up workout for Rebecca Mehra, a young middle-distance runner with Oiselle’s Little Wing pro group in Bend, Oregon: a 500, a 300, and a 200-meter rep at the relatively relaxed pace of 69 seconds per lap. It was early June, with the biggest and fastest meets of the 2019 summer season looming. But it soon became clear that Mehra couldn’t hit the splits. And she wasn’t just slow. Something looked… off. “It was like she was sticking to the ground on each step,” her coach, Lauren Fleshman, recalls. “It wasn’t like a normal tired thing. It was like everywhere there would normally be a taut spring in a middle distance runner’s stride, there was now a used-up slinky.”

Accumulated fatigue is an occupational hazard for hard-training elite runners, so Fleshman and Mehra made some adjustments, hoping that with a bit of rest she’d bounce back. But her next workout ended in tears when she couldn’t even hold her usual mile race pace for a 200-meter rep. Fleshman pored over her training records looking for a clue, and asked probing questions about what else in Mehra’s life might be affecting her. It wasn’t until almost a week later that Mehra mentioned something she had recorded in her training log as “the electrocution incident.” “I remember her being pretty offhanded about it,” says Fleshman, “like just an afterthought.”

The control panel on Mehra’s oven was broken, causing it to beep incessantly, so she’d gotten in the habit of unplugging it when it wasn’t in use. After cooking dinner a few days before the 500-300-200 workout, she was reaching behind the oven to yank the plug out when—zzzzap! Suddenly 240 volts were coursing through her left hand, up the arm, and down through her feet to the floor. “For what felt like three or four seconds I wasn’t able to let go of the plug,” she recalls, “as if my hand was glued to it.”

Roughly 10,000 people a year show up at U.S. emergency departments with electrical injuries (“electrocution,” strictly speaking, only refers to fatal incidents), mostly toddlers, risk-seeking adolescent boys, and people who work with electricity for a living. Lots more people get shocked but don’t seek medical attention: one study found that only 32 percent of electricians who were thrown across a room by a shock bothered to go to the hospital. (Of those who were knocked unconscious, 92 percent decided to get checked out—which still seems pretty low!)

The consequences of these shocks can vary enormously, depending on the type and amount of electricity and the path it travels through your body. According to the International Electrotechnical Commission’s Effects of Current on Human Beings and Livestock, roughly half a milliamp is enough to elicit a reaction from most people. Pain starts around 1 milliamp; by 10 milliamps, you’re approaching your “let-go threshold,” the point at which an involuntary muscle contraction makes it impossible to open your hand and release whatever is shocking you; by 50 milliamps, you’re in danger of stopping your heart if the current passes through it. Electrical burns are a serious issue, and, for reasons that remain unclear, neurological problems can surface in the days or months following an electrical injury even if the current didn’t pass through the brain.

But it’s not entirely clear what any of that has to do with running at mile race-pace. In the days following the incident, Fleshman hunted for explanations of Mehra’s loss of form, but came up empty-handed. That’s not surprising: even to experts, electrical injuries, at least those that don’t simply kill you, remain largely mysterious and poorly understood. Mehra herself, after finally managing to release the plug, lay on the floor in a swirl of worry and confusion for a few moments. But other than the fact that her hand was physically shaking, she felt fine in the moment—so she simply carried on as usual.

I first heard about Mehra’s “incident” last fall, after the track season ended. When I started getting in touch with physiologists and experts in electrical injuries around the world to ask how they might explain her symptoms, the general answer was more or less unanimous: we don’t know. Even under the best of circumstances, making any sort of diagnosis would have been hard; distance and the passage of time made it impossible. But when I persisted, several people agreed to speculate, and their speculations fell into two basic categories.

The first possibility is that the muscles themselves were damaged. Essentially, the flow of electricity through the muscles could have caused muscle cells to burst, giving her a relatively mild case of rhabdomyolysis, a potentially serious condition that can also be triggered by extreme workouts. This could explain Mehra’s struggles on the track, says Chris Davis, an associate professor at the University of Colorado School of Medicine and lead author of the Wilderness Medical Society’s guidelines on lightning strikes: “There just aren’t the same number of functioning muscle fibers left to do the work of running.”

A related possibility is indirect muscle damage, caused not by the current itself but by the after-effects of the vigorous muscle contraction triggered by the shock. In this case, it’s as though Mehra did a super-intense all-out leg press with no warm-up, leaving her with the equivalent of classic delayed-onset muscle soreness for a few days.

An intriguing twist about this theory: normally when you contract your muscles, you start by recruiting easy-to-trigger slow-twitch muscle fibers, and only progress to the heavy-duty fast-twitch fibers if you need them. But contractions triggered by external electrical stimulation occur in the opposite order, notes University of Kent physiologist Mark Burnley. If Mehra’s fast-twitch fibers were the ones most weakened or damaged, that could explain why she didn’t notice any problems until she headed to the track and tried to sprint at race pace. Arguing against this theory, on the other hand, is the fact that her legs didn’t feel noticeably sore.

The second main option is that the problem was in the nerves that conduct signals from the brain to the muscles, which might have been damaged by the electrical current flowing through the limbs or even along the spinal cord. Nerves are specifically designed to carry electrical impulses, so they’re an obvious path for electrical current to flow along during a shock. “This is way more of a black box,” says Davis. “We really don’t understand all the ways that electrical or lightning injuries manifest in the nervous system.”

Chris Andrews, an expert in electrical injuries at the University of Queensland in Australia, also sees nerve damage as a likely culprit. In his experience, prolonged weakness and extreme fatigability of muscles in the line of current are common symptoms. “Many of the disabilities look like nerve damage, but testing is not always fruitful,” he says. It’s possible that there’s a type of nerve damage that current testing can’t detect; Andrews suspects the problems may occur in the junction between nerve and muscle. Based on the information available, that seems like the best explanation for why Mehra didn’t feel any particular muscle soreness, but nonetheless looked and felt as though she was running on a pair of used-up slinkies.

Even without a diagnosis, Fleshman and Mehra realized they needed to back off and let her body recover. They slashed her training from 60 miles a week to low 40s, and within about two weeks she started to come around. In her first race back, she gutted out a decent 4:12 1,500, within a second of her best time, at the Portland Track Festival—a confidence booster, in a strange way. “I proved I can still step on a track when I feel awful and run a very solid race,” she noted on her blog.

Then she went on a tear. As the 17th seed at the USATF championships, she surprised everyone by making the final. On a European tour later that summer, she pushed her personal bests down to 2:02 for 800 meters and 4:08 for 1,500 meters. She finished the year by taking third in a world-class field at the Fifth Avenue Mile in 4:22. She’s now gearing up for a run at the Olympic team this summer, and she even got the oven fixed.

As for whatever happened to her last June, there’s one thing all the experts I spoke to agreed about: she’s lucky. It’s impossible to get stats on how many people have accidents like this and never go to the hospital. But for those who do seek medical attention, the symptoms sometimes linger for months or years, and are sometimes permanent. There aren’t many examples in the literature of people who, a few weeks later, are somehow better than ever. “I am very glad that Mehra has recovered well, and has gone on to good athletic success,” Andrews says. “This is not always the case.”

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