Not Every Run Goes Off Without a Hitch. Here Are 11 Common Things That Could Go Wrong and How To Handle Them Like a Pro

These satisfying, borderline-easy runs inspire us to attempt longer distances and chase after new PRs. We lace up again and again, hoping to tap into that natural sense of flow.

The opposite experience—the runner’s low, if you will—is less majestic but much more common. If you’ve been running for any amount of time, you’ve likely found yourself in the trenches of a run gone wrong.

Due to unforeseen circumstances (think: blisters, cramps, and gastrointestinal issues), every step is more miserable than the last. You tell yourself that if you somehow make it to the finish line, you will seriously consider hanging up your sneakers and never running again.

The good news is that most runners persevere and, better yet, learn how to prevent and manage running mishaps during future workouts and races.

To help you get ahead of some of the most common issues plaguing runners, we asked a handful of coaches to share their advice for avoiding such annoyances and, when necessary, how to roll with the punches. Keep their words in mind the next time you find yourself trudging through your own running nightmare.

Friction issues

Many problems arise from gear literally rubbing runners the wrong way. Even apparel, socks, and shoes specifically designed for running can cause problems. But there are some tried and true preventative tactics and mid-run workarounds.

Blisters

“Unfortunately, by the time you feel a blister coming on, it’s probably too late,” says Todd Buckingham, PhD, triathlete and exercise physiologist at PTSportsPRO in Grand Rapids, Michigan. It’s already formed, and the best you can do is minimize any further irritation.

If you’re running a race, aid stations often carry anti-chafing cream and adhesive bandages, which you can use to protect the area. (Though bandages can sometimes increase friction, as they add another layer of material, Buckingham warns.) Otherwise, stop to inspect your socks, as seams and bunched material are often to blame for blisters.

Next time, make sure your running socks are made of sweat-wicking material, and check the fit of your running shoes—they may be too tight or too big (sliding back and forth is just as bad as rubbing and pinching). If you tend to get blisters in one area, try applying a bit of lubricant, like Body Glide ($11), before heading out. And allow all new shoes a “breaking in” period of shorter, low-stakes runs.

Chafing

“There’s a reason people don’t run in sweatpants and T-shirts anymore,” Buckingham says. Cotton fabrics, while comfortable for lounging, can trap moisture and create chafing “hot spots” in high-friction areas, like your armpits, inner arms, groin, and thighs.

As with blisters, the key to preventing skin chafing is to wear properly fitting running gear constructed with sweat-wicking fabric. That said, fit and quality vary, and even the most expensive specialty gear can cause issues. Give every new piece—even sports bras and underwear—a short trial run before wearing it during a race or lengthier training run.

Chafing mid-run? Again, if you have access to supplies, a dab of anti-chafing ointment or even a bit of petroleum jelly can reduce rubbing and provide some relief.

Black toe nails

Amber Rees, RRCA and VDOT-certified running coach, co-founder of Brave Body Project and chief instructor at Barry’s NYC, jokes that a black toenail is a “runner’s rite of passage.” “Although they can be painful and even ruin your socks and cute sneaks,” she says.

Toenails typically turn black or bluish in color when blood collects beneath the nail. “It usually occurs from your feet sliding within your shoe, which causes your toes to slam against the front of your sneaker,” Rees says. “This may mean you need to switch to a different sock, try a different shoe, or try the runner’s heel lock.” The heel lock, Rees explains, is a shoe-lacing method that secures your ankle in place and keeps your foot from moving back and forth.

Black toenails don’t typically appear after one run; you can usually prevent them by paying attention to feelings of pain or numbness in the toes and troubleshooting before your next workout.

Also, keep your toenails trimmed.

Fueling and hydration snafus

Running requires adequate hydration and nutrition, yet consuming food and liquid before, during, or after a run can be tricky. So much can go wrong…terribly, terribly wrong.

Nausea and vomiting

“In the early stages of your run, your body is working overtime to pump blood to your muscles,” explains Lindsey Clayton, RRCA and VDOT-certified running coach, co-founder of Brave Body Project and chief instructor at Barry’s NYC. “This reduced blood supply to your digestive tract could result in [gastrointestinal] distress.”

Meal timing and food choices often play a role in exercise-induced digestive issues. It may take some experimentation to determine your ideal pre-run snack, but it’s generally a good idea to avoid high-fiber foods and stick to easy-to-digest carbohydrates versus fats and protein. Allow yourself at least an hour between your last bite and your run. And if you need to refuel mid-run, simple carbs, like energy gels and gummies, are often your best bet. (Just make sure you test them out before a big event.)

If you’re hit with stomach cramps or nausea during a run, sometimes slowing down to a walk and focusing on your breathing can help settle queasiness. Vomiting can lead to fluid loss, so if you do lose your lunch, take a break and sip some water or an electrolyte drink.

Runner’s trots

Like nausea and vomiting, “runner’s trots,” aka diarrhea, is often triggered by fueling mistakes, like consuming too much fat or fiber or eating too close to your run. Prevention often comes down to trial and error, as every runner (and their digestive system) is different. (A bowl of oatmeal may keep your running buddy feeling fueled for miles, but it may have you running for the nearest toilet.)

It’s also important to stay consistently hydrated. “You’re already sweating and losing fluids, and if you’re not adequately hydrated, your chances for stomach cramps, nausea, and diarrhea may increase,” Clayton says.

Slowing your pace or taking a walk break may alleviate a sudden urge to poop, but sometimes it makes sense to hit up the nearest bathroom or porta-potty (or wooded area, if you’re in a remote area), even if it adds a few minutes to your time. “I might argue that not stopping will cost you more time because you’ll be walking or not running as fast because you’re trying to deal with it,” Buckingham says.

Dehydration

The key to staying hydrated during a run is to play the long game. It’s not enough to drink fluids right before, during, and after a run, explains Raj Hathiramani, certified running coach with Mile High Run Club in New York City. “The most important ritual is to hydrate as early as 48 hours before a hard training run or race,” he says. “[Consume] water plus electrolytes to prevent dehydration, cramping, and heat-related conditions.”

Just how much water you need depends on various factors, like your body weight, your level of physical activity, the salt content of your sweat, and the climate. One easy way to monitor your hydration level is to pay attention to the color of your urine. It should be light yellow, like lemonade. Anything darker or noticeably smelly is your cue to increase fluid intake.

If you experience signs of dehydration on a run—thirst, fatigue, headache, and an elevated heart rate are common—seek water or a sports drink that contains electrolytes. “If you don’t have access to water and electrolytes, adjust your effort to a slower pace or walk and try to procure fluids if you intend to keep up your activity,” Hathiramani says.

Fatigue

Fatigue may be a sign of inadequate fueling and hydration. But if every run feels like an uphill battle, even when covering flat ground, the issue may be your recovery.

“Persistent fatigue is often due to the lack of adequate rest and recovery, which are important to maintain good mental and physical health as well as optimal performance,” Hathiramani says. “The longer and harder your training routine, the longer the rest and recovery you may need.”

He notes that it’s tricky to address fatigue in the moment; the best you can do is slow your pace or incorporate periodic walking intervals. To address the root issue of your ongoing fatigue, you need to make structural changes to your training.

“Don’t increase weekly mileage too drastically. Avoid training programs that are too long to prevent both mental and physical fatigue. Find a better balance between running and cross-training, speed-work, and easier effort runs,” Hathiramani says. “Finally, plan complete rest days or a full week, a massage. Listen to your body and resume training with renewed strength.”

Many problems arise from gear literally rubbing runners the wrong way. Even apparel, socks, and shoes specifically designed for running can cause problems. But there are some tried and true preventative tactics and mid-run workarounds.

Cramps and stitches

When it comes to managing sudden muscle cramps and side stitches, a good defense is often the best offense. And when that fails, take a deep breath.

Muscle cramps

As an exercise physiologist, Buckingham has studied muscle cramps. “For how prevalent muscle cramps are in the population, we really don’t know exactly what causes them,” he says. “It could be like dehydration. It could be electrolytes. It could be the carbohydrates you have available. It could be how fast you’re running, if you are not running appropriate paces. It could be a neurological issue. And probably the best explanation of all is that it’s some type of combination of all of those different things.”

Proper fueling and hydration, progressive training, and warming up before a run may help prevent cramping. But you could do everything right and still seize up. In that case, “start by adjusting your breathing and physical effort to help your muscles relax,” Hathiramani says. “In addition, take in adequate fluids and electrolytes in case you are dehydrated.” Ingesting some carbohydrates, like an energy gel, may help, too.

Side stitches

Research¹ on the side stitch isn’t conclusive. Sudden, sharp abdominal pains may be related to a runner’s breathing patterns, digestion, hydration, biomechanical issues, or level of physical fitness.

Covering your bases from training, fueling, and hydration perspectives may ward off side stitches. Hathiramani also recommends rhythmic breathing. “This technique coordinates your foot strike with inhalation and exhalation in an odd/even pattern, so you land alternately on your right and left foot at the beginning of every exhalation when your diaphragm relaxes, and you have less stability in the core,” he says. “This is done to balance the impact stress of running on both sides of your body. Always exhaling on the same foot is similar to carrying a backpack on only one shoulder.”

If, despite your best efforts, you still get a stitch, Hathiramani recommends inhaling and tightening the abdominal muscles on the side of the stitch. Hold for a few seconds, then relax. Repeat until the stitch dissolves. Stopping and stretching the arms overhead may also help.

The elements

Between scorching temps and uneven terrain, it can feel like the world is working against you. Learn to protect yourself and minimize impact.

Sunburn

“I recently experienced this,” Clayton says. “I didn’t anticipate the 2024 Boston Marathon to be 80 degrees and sunny in April, but that’s what we got on race day. The entire back side of me was so sunburned—my calves and shoulders peeled for weeks.”

Always wear sweat-proof SPF (even when it’s cold and cloudy), and use a hat and sunglasses to protect your eyes and face. If you realize you missed a spot or need to re-apply during a race, check an aid station for SPF. If you find that you’re burning up during a training run, consider re-routing to a shadier area.

Rolled ankle

It happens so quickly. One minute, you’re trucking along, and the next, your ankle is the size of a small cantaloupe.

Tree roots, potholes, and uneven sidewalks are often to blame for rolled ankles. But if you’re dealing with repeat injuries, take a look at your footwear, as extra cushioning may be contributing to balance issues. You may also want to incorporate more lateral movements, glute strengthening (some research² shows a correlation between weak glutes and ankle instability), and balance work into your cross-training.

You’ll know almost immediately if a rolled ankle is one that you can “shake off” or if it’s more serious. If you’re unable to bear weight or feel sharp pain, get yourself to a medical tent or call for help.