Stop googling and check out these expert-sourced solutions for all those less-talked-about (yet still totally distracting) running issues you've never been able to understand.

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If you're an avid or even just a recreational runner, chances are you've experienced an injury of some kind in your day. But outside of common running injuries like runner's knee, stress fractures, or plantar fasciitis that can keep you sidelined, there's also a slew of annoying and often painful symptoms many runners experience that are less-known and rarely talked about. We're talking about things like a persistently runny nose, itchy legs, or pain in your teeth-the kind of thing you google after a run to figure out if anyone else in the world has experienced the same thing and if there's anything you can do about it.

Well, good news: You're not alone. So, stop freaking out. Check out our expert-sourced solutions for all those strange running-specific issues you've never been able to understand.

You have a metallic taste in your mouth.

Why it happens: Ever experienced a weird metallic or bloodlike taste in your mouth while out for a long run? This is likely the result of you pushing yourself beyond what your body can handle at your current fitness level, says Josh Sandell, a sports medicine specialist and chief clinical officer to Orthology. When you exert yourself, red blood cells can accumulate in the lungs. Then some of those red blood cells (which contain iron) are transported to your mouth through the mucus, leading to that odd metallic taste, says Sandell.

How to fix it: If you're trying to do too much too quickly, take it back a notch and give your body a chance to adapt to your new running load. If you didn't significantly overdo it on a run or are experiencing additional symptoms such as shortness of breath, seek out a medical professional, since this symptom could also indicate that your heart is underperforming. Regardless, "a metallic taste in the mouth during running is not something to be overlooked," he warns.

Your foot falls asleep.

Why it happens: If your foot falls asleep while you're sitting at your desk, you probably don't think anything of it. But when it happens while you're out on a run, it can be painful, not to mention a bit scary. The (somewhat) good news is that foot numbness is typically a nerve-related condition having to do with your shoes, says Tony D'Angelo, a licensed physical therapist and certified athletic trainer who has worked with professional athletes. (FYI, wearing the wrong shoes is one of the eight mistakes every runner makes.)

How to fix it: Check the size of your running shoe. Most runners need sneakers that are a full size larger than street shoes to leave room for the feet to expand while running, says D'Angelo. If sizing up doesn't help, look at the placement of the stitching or padding or consider trying out a totally different brand.

You feel pain between your toes.

Why it happens: Pain beneath or between the toes is usually caused by something extrinsic in your routine-maybe your stride or again, the type of shoe you're wearing, says Sandell. If your toe box is too narrow, it may constrict your toes and cause compression on the nerves that run in between your toes, which can cause you pain or even numbness. If the pain seems to be coming from beneath your toes, you may be relying too much on forefoot running, causing increased compressive forces that accumulate throughout your run, he says.

How to fix it: Have someone reassess your running sneaks. You may be able to alleviate your pain by simply finding a shoe with a larger toe box to allow your feet to swell during running (a totally normal side effect), says Sandell. And while forefoot running may be the right technique for you, be sure you aren't running too far forward on your toes-that can cause undue stress. (Related: How to Determine Your Running Gait-and Why It Matters)

Your nose is runny.

Why it happens: If you consistently have a runny nose only while running, and have ruled out a medical condition like nasal polyps, or an infection, you can assume that you have exercise-induced rhinitis, says John Gallucci, a physical therapist and sports medicine consultant to pro athletes. This looks a lot like allergic rhinitis (aka hay fever or just plain old allergies) and may cause symptoms such as a runny nose, congestion, and sneezing during an intense workout. These symptoms are usually more common in the winter, in people who already have a nasal allergy, and in people who usually exercise outdoors, says Gallucci. And while it won't cause you any harm, it can definitely be super annoying having to remember to bring tissues every time you head out. (Related: 5 Things Physical Therapists Want Runners to Start Doing Now)

How to fix it: To help reduce the symptoms, try using a nasal spray before you head out for your run, he says. And since exercise-induced rhinitis is more common outdoors, try running inside or far away from any busy streets where the nitrogen dioxide may be elevated from car exhaust, adds Sandell.

You feel pain in your shoulder blades.

Why it happens: Ask enough runners (or troll Reddit), and you'll see that pain in the shoulder blade-on the right side specifically-is actually a pretty typical complaint. "One of the most common reasons why runners experience this is because they are subconsciously pulling the shoulder blades in as they run, which creates increased tension in the shoulder blade and neck region," explains Kirk Campbell, M.D., a sports medicine surgeon and assistant professor of orthopedic surgery at NYU Langone Medical Center. If these muscles remain contracted for prolonged periods of time, this can lead to pain and discomfort, says Dr. Campbell.

How to fix it: If it sounds like you fit into the above category (and you don't experience shoulder pain outside of running), the good news is your fix is simply a matter of working on your form, he says. It may be worth investing in a few sessions with a running coach to ensure that you nail down the proper running technique. But you can make improvements on your own by focusing on keeping your shoulders relaxed and by being aware of how you swing your arms, he adds. (Related: How to Calm Red Skin After a Workout)

Your legs are itchy.

Why it happens: This sensation, known as "runner's itch," can occur in anyone who is performing intense cardio, not just runners. And it can spread beyond the legs too, explains Gallucci. Once ruling out other causes, like the possibility of an allergic reaction, skin condition, infection, and nerve-related disorder, this sensation can be attributed to your body's natural reaction to increased heart rate during exercise, he says. Here's how it works: "As your heart rate increases, the blood flows more rapidly, and your capillaries and arteries within your muscle begin to expand rapidly. These capillaries stay open during exercise to allow for adequate blood flow. However, this expansion of capillaries causes the surrounding nerves to become stimulated and send alerts to the brain which recognizes the sensation as itching." (Related: 6 Things I Wish I'd Known About Running When I First Started)

How to fix it: Runner's itch is experienced by those who are starting a new exercise program or who have fallen off the wagon for an extended period and are getting back into cardio, Gallucci says. In other words, the solution for this one is pretty easy: Start running more. Good news, though: "Just as your skin may turn red when exercising, itchy legs is no reason for concern unless the itchiness is accompanied by hives, difficulty breathing, swelling of the tongue or face, or severe stomach cramps," Gallucci adds. In those cases, stop running and head to a doc immediately.

You have pain in your neck.

Why it's happening: Pain at the base of the neck is another common complaint that is usually the result of bad running form, says D'Angelo. "If you forward lean when running, it places extra stress and strain on the spinal muscles in the upper neck and lower back," he explains. Yes, it's annoying while you run, but over time it can also predispose these muscles to injury.

How to fix it: Run with your shoulders down and relaxed (not up at your ears), and keep your chest thrust upward, says D'Angelo. Think tall when running and this will help improve most of your poor form-especially when you start to fatigue, he says. Another tip to improve your form and reduce the risk of injury? Amp up your cross-training that is focused on building strength and flexibility in your upper body, neck, and core region, advises Dr. Campbell.

Your teeth hurt.

Why it happens: Tooth pain on a run can range from slightly distracting to completely debilitating. If you've seen a dentist and ruled out other dental issues like an abscessed tooth, your tooth pain may be caused by grinding your teeth-otherwise known as bruxism, says Sandell. While it typically happens during sleep, this subconscious reflex can also kick in during stressful situations and even during exercise, especially if you're really straining yourself to finish that last mile. In addition to tooth pain, grinding your teeth can also lead to headaches, pain in the facial muscles, and a stiff jaw, he says.

How to fix it: Focus on keeping your jaw relaxed while you run-breathing techniques can help. Or consider wearing a mouth guard when you work out. (Related: Why You Really Cough After a Tough Workout)

The inside of your ear aches.

Why it happens: Exercise-induced earaches can be somewhat common to long-distance runners, especially when running in the cold or at high altitude, says Sandell. As you've likely experienced, high-altitude running can cause pain because of the difference between the outside pressure and the pressure in your inner ear. Meanwhile, cold air can cause the blood vessels to constrict and, therefore, limit the blood flow to the eardrum, which can cause pain.

How to fix it: Besides covering your cold ears with a hat or headband, you can try popping some gum on your next run. The chewing motion can stretch the inner ear, nose, and the tube that connects the two to help normalize the pressure difference between the altitude and your ear, he says. (Related: Why Some Workouts Make You Feel Like Throwing Up)

Your fingertips swell.

Why it happens: This sounds strange, but swollen fingers are a common, natural response to an elevated heart rate, which causes the body to send out more blood to muscles to assist with the increased workload, Gallucci says. "Our hands have many blood vessels that expand during exercise, and the increased blood flow can cause pooling of blood in the fingers," he explains. To complicate matters, though, there are a few other possible causes. If you're an endurance athlete, swollen fingers may be because of drinking too much water (which causes sodium levels to become depleted and affects the efficiency of blood flow), or alternatively, because you aren't hydrating enough pre-workout, causing your body to reserve the fluids you do have available in storage.

How to fix it: While running, try not to clench your hands tightly, but rather keep them relaxed and slightly open. It's also helpful to perform hand pumps (opening and closing of hands), or to raise your hands above your head or to perform arm circles every couple minutes to help with circulation if you're really struggling. And of course, be sure to adequately hydrate, with endurance athletes taking extra precaution to balance salt and water intake.