top of page

Injury risk from carbon-plated supershoes

OCT 13, 2023

Minute 1: Stephanie Bruce catches heat for running while pregnant (Whaaaat?!?!)

We’ve got all the respect in the world for distance runners, but compared to the stamina and endurance required of mothers, running a marathon can seem like a walk in the park. That’s why we find it odd when people make a big stink about women who continue to run and exercise during pregnancy. Despite getting approval from her doctor, elite distance runner Stephanie Bruce faced quite a bit of backlash for staying active through her pregnancy, and you can watch her story in this video created by the New York Times: “I Ran While Pregnant. The Internet Had Thoughts.” When speaking to her doctor, Staphanie was told: “You’ll know. Trust your body, it’ll know what to do.” For some runners, that means they can continue to run with intensity well into their pregnancy, like this remarkable woman: “Pregnant runner ran a mile in under 6 minutes shortly before her due date.” For most people, you’ll probably want to dial things back a bit, but a good rule of thumb is that if you were active before your pregnancy, you can expect to maintain a similar level, at least in the early stages, according to this piece: “Exercise During Pregnancy.” Despite what you may have heard, exercising while pregnant does not put you at increased risk for miscarriage in normal cases. If your doctor says it’s safe to do so, feel free to keep logging miles. After all, the legendary Joan Benoit Samuelson ran two marathons while pregnant and even logged six miles on the day her son was born.

Minute 2: Walks are good for the heart, mind, and body

Fans of rom coms like “When Harry Met Sally” know that there’s nothing quite so magical as falling in love. Through a Hollywood lens, who doesn’t want what Sally’s having? But if you don’t want to wait 12 years to finally reach relationship nirvana, like Billy Crystal and Meg Ryan’s characters, there is a shortcut to replicating how they felt, according to this new story: “The Lifestyle Change That Simulates ‘Falling in Love’.” Walking is one of the most effective ways to reduce stress, boost mood, and increase your life satisfaction. So much so that researchers have compared the effects to that of getting into a new relationship. The honeymoon phase is one of excitement and joy, and if you set your life up to involve lots of walking commutes, it's a phase that never has to end. By choosing a job that’s within walking distance or moving to a city that prioritizes walkability and pedestrian safety, you could live a longer and healthier life. Not only that, but walking can be a surprisingly effective core workout when you follow these “7 Easy Ways To Turn Walking Into a Workout for Your Abs.” The core muscles are engaged when our body needs to be stabilized. That means you can target core muscles by adding some movement to your walk by swinging your arms vigorously. If you’re looking for even more of a challenge, carry small dumbbells or pack a bag full of weight and participate in “rucking.” For more on that, take a look at “Rucking is an easy way to fitness.”

Minute 3: Master your marathon recovery

Fall is here, temps are cool, and the marathon season has begun. Whether you’re running 26.2 miles in a local race or a World Marathon Major, the physical demands are the same, and you’re going to want to know the “10 Best Marathon Recovery Tips” to make it through autumn in one piece. The first thing you should do after a marathon (or any race, for that matter) is rehydrate, and that goes beyond simply drinking enough water. You’ve got to replenish electrolytes too, and you can see how that’s done in this advice from Trail Runner: “The Runner’s Complete Guide To Electrolytes.” Look for food and drinks that contain sodium, potassium, calcium, and magnesium to give yourself a smooth recovery. Next on the list is trying the classic “legs up the wall” trick. Experts no longer think this does much to drain lactic acid out of sore muscles, but it does promote blood flow which is essential for bringing nutrients and oxygen to your damaged tissue. For more on that, take a look at: “The Yoga Pose You Need: The Health Benefits of Legs Up the Wall.” The last tip we’ll mention is prioritizing sleep. Some runners prefer to take a 20-minute nap after their race and a carb-heavy meal. However, if you find that napping disrupts your ability to fall asleep later on, you should avoid it, as keeping a consistent sleep schedule is one of the most important factors for getting quality rest, according to: “The 7 golden rules for marathon recovery.”

Minute 4: Shoe Analysis: Can carbon-plated racing shoes increase the risk of injury? (Unfortunately, yes.)

As much as the new generation of supershoes have lowered marathon times while increasing shoe company stock prices, we need to use caution in how we use these shoes in our training, according to our shoe guru Brian Metzler and a host of other experts. A few highlights of Brian’s analysis of the safety of supershoes is below, but check out the full story on our website.

Supershoes have led to several world records in the marathon, including the new women’s mark of 2:11:53 set by Ethiopia’s Tigst Assefa wearing Adizero Adios Pro Evo 1 shoes on September 23 in Berlin and the new men’s mark of 2:00:35 set by Kenya’s Kelvin Kiptum wearing a pair of Nike Alphafly 3 prototypes on October 8 in Chicago.

But one of the big questions being asked with more regularity is whether or not those shoes make runners more susceptible to injuries. To date, no substantive academic research has been done on biomechanical impacts of carbon-fiber shoe technology on a runner’s gait as it relates to injuries. But elite athletes and recreational runners alike, as well as some coaches and medical professionals close to the sport, have become increasingly concerned about the correlation between those types of shoes and running injuries. We have seen anecdotal evidence of foot pain, Achilles tension and sprained ankles associated with the use of supershoes.

Back in February, Sports Medicine published a scientific opinion piece that opened a dialogue about the possibility that runners might be susceptible to foot injuries from running in shoes with carbon-fiber propulsion plates. In the report, led by Adam Tenforde, M.D., a Boston-based physician at Mass General Brigham’s Sports Medicine program and medical director of the Spaulding National Running Center, researchers studied the cases of five athletes who had been diagnosed with stress injuries to the navicular bone – a bone at the medial side of the highest point of a runner’s arch – to determine if there might be a biomechanical plausibility tied to the novel stresses related to shoes with carbon-fiber plates.

Tenforde, working with peers at the Sports Medicine Department of the Palo Alto Medical Foundation in Palo Alto, California, and the Institute of Interdisciplinary Exercise Science and Sports Medicine in Hamburg, Germany, made clinical observations of three teenage middle-distance track runners in Europe and two athletes in their late 30s who competed in running races and triathlons in North America. They determined that three of the athletes developed foot pain after little or no adaptation to the racing shoes, but two of the athletes reported chronic pain after extensive training time in carbon-plated shoes.

While the report was essentially based on a series of singular case presentations – there was no control group and no testing specific protocol for each of the athletes – Tenforde says he believes it can be a valuable first step for runners, the running shoe industry and the medical community to understand the altered biomechanical demands of running in shoes with carbon-fiber plates.

Amol Saxena, a leading sports podiatrist in Palo Alto, California, told journalist Jonathan Beverly recently that the problem with the carbon-plated shoes is that your foot is individualized, and the carbon plates are not. “So if the shape or length of your metatarsals line up differently than where it has to bend, or your plantar fascia is less flexible, you can get stressed in those areas—that’s why people are breaking down. I’ve had people break or tear things just in one run in the shoes.”

In other words, carbon-plated racing shoes put runners in less stable situations compared to their training shoes, Dicharry says, and that can put a runner’s feet, lower legs and knees into compromised positions as they roll through the gait cycle that makes it even harder to absorb those increased loading rates. And, given that the stride pattern of most runners tends to be somewhat unstable to very unstable to begin with, wearing carbon-fiber shoes too often without optimal adaptation can increase the likelihood for a variety of stress-related injuries.

The bottom line is that runners should adapt gradually before deciding to do speed workouts, tempo runs and long runs in carbon-plated racing shoes, Dicharry says. But if you have poor running mechanics or unstable foot placements and start running in those shoes without adapting, it will greatly accentuate the problem.

For Brian’s full take on the safety of supershoes, check it out here.

Minute 5: Quick Intervals

  • Rebecca Trachsel, our SMM DJ, just published an entertaining account of running the Cape Cod Marathon last weekend. Having battled mono and various injuries leading up to the race, Rebecca was OK with the idea of running rather than competing in the race. Even with that healthy attitude, however, the day was almost ruined for this music devotee when she realized she’d forgotten her headphones. Rebecca shares her solution to that problem and an excellent race recap here on the Running With Music blog. As for her latest running playlist recommendation, today's song is "My Whispers Are Wildfire" by Ida Mae. The band is composed of husband and wife duo Chris Turpin and Stephanie Jean from the UK. “Whispers” is off their second album, "Thunder Above You" which was released this past August. Jean's voice is smooth and sultry but it's Turpin's guitar that mesmerizes. Listen to the whole song start to finish and then listen again as you hear something new and different each time. They are labeled folk/blues, a category you may not usually throw into your running mix. This time I think you will. Link to the song on Soundcloud is here and the link on Spotify is here. #turnitup

  • If you’ve ever contracted a cold or the flu that just wouldn't quit, you may have experienced something called “long flu.” If that sounds familiar, that’s because it gets its name from the dreaded “long Covid.” In researching long Covid, scientists discovered that lingering symptoms from other similar diseases are more common than we thought. To learn why, and what to do about it, read “You Can Get 'Long Colds' and 'Long Flu,' Too.”

  • Kelvin Kiptum may have had the most meteoric rise in distance running history. He debuted in the marathon in 2022 with a time of 2:01:53. Merely a year later, in his third ever marathon, Kiptum broke the world record, immediately drawing comparisons to his closest competitor, Eliud Kipchoge. Some fans say he’s already cemented himself as the marathon GOAT, while others say it takes consistency, above all else, to earn that title. To hear more on the debate, read this piece from Outside: “No, Kelvin Kiptum Is Not the Next Kipchoge.”

  • In his new book, Arnold Schwarzenegger shares the story of how WD-40 got its name. It’s quite simple: “WD” stands for “water displacement,” and the formulas for WD-1 through 39 were failures. What does that have to do with becoming a world-renowned bodybuilder or governor of a major state? Well, it's a good reminder that failures are a necessary part of the journey toward eventual success. If you want tips on embracing failure as an athlete, or any other aspect of life, take a look at: “Arnold Schwarzenegger Shares How to Reframe Failure.”

Minute 6: Daily Inspiration

We’ve always felt it takes a patient person to fall in love with distance running. If you’re someone who needs instant gratification, it’s probably not for you. Confirmation that runners are cut from a different cloth was confirmed by one study that @therunningeffect highlighted in a recent video. Runners were told to submerge their arms in ice water for as long as they could stand, and when compared to non-athletes – and even soccer players – they were significantly more capable of withstanding the discomfort. You will learn the details and pick up some inspiration for enduring the “pain cave” in the video below. Click here to watch.


bottom of page