Sore muscles or serious injury? What every runner needs to know

January 30, 2015                 6m read time
Kathy Murdock

A nagging back. A sore knee. A hamstring that feels like it’s on fire. Should you RICE (Rest, Ice, Compression, Elevation)? Continue to run but slow down the mileage and pace? Or is it time to call in an expert and shell out a co-pay for an examination? Here's how to separate the good pain from the bad.

Grin-and-bear-it mantras like “No pain, no gain” and “Pain is weakness leaving the body” are all too familiar to most runners. Some runners even welcome pain, as they believe conquering the aches will make them stronger, faster, better on the pavement. Although toughing it out to finish a challenging run can leave you feeling invincible, pain is not always something runners should “push through” and “get over.”

In fact, pain means your body is signaling your brain that something might be wrong. Sure, it may be nothing more than an IT band that needs some foam roller love. But it might also be a torn meniscus, which could require surgery and months of rehab if not cared for properly.

The key is knowing how to differentiate between sore muscles and pain that might indicate a serious problem. To help you sort through your body’s signals, we’ve compiled a list of some of the most common running injuries, what they feel like, and when you should head to the doctor.

Plantar fasciitis

While the pronunciation may sound unusual (it’s fas-e-I-tis, by the way), the injury itself is actually quite common. Plantar fasciitis, or PF, is inflammation of the plantar fascia, which runs on the underside of your foot from your heel to your toes. PF causes stabbing heel pain in the early morning when you first take a step or two, but the pain typically recedes after you’ve moved around a bit. Continuing to run can cause chronic pain or can change your gait, which will then create different problems in other parts of your body. Physical therapy, stretching, and rest can help ease the pain.

Shin splints

If the front of your lower leg is aching, you might have developed shin splints, which is an inflammation in the tendons, muscles, and bone tissue around your tibia. These happen when runners increase mileage or pack on too many speed workouts. This inflammation is not to be confused with stress fractures (see below). Rest and ice help alleviate discomfort caused by shin splints.

Stress fractures

Stress fractures are one of a runner’s biggest fears when it comes to injuries. In runners, these tiny cracks typically occur in the tibia or shin bone, followed by the metatarsals, the bones behind the toes. An overuse injury, stress fractures are often caused by too much force to the bone, as when a runner increases mileage quickly or trains harder than normal.  

Stress fractures can, over time, cause swelling (especially on the top of the foot in a metatarsal fracture) and intense pain, though in the beginning they may not cause much pain at all. Stress fractures tend to progress from a more general pain around the injury to an increasingly localized pain. Pay attention if you have pain that worsens as your run progresses or a throbbing type of pain after the run is completed.

If you have any of these symptoms, see a sports medicine specialist right away. Because they aren’t complete breaks in the bone, these cracks often go undetected on traditional X-rays, so it’s important to follow-up with a bone scan, CT scan, or MRI.

Treatment includes rest and ice. Additionally, a cast or boot may be used to keep weight off of the area of fracture.  

ITB pain

Iliotibial band pain, more commonly referred to as IT pain, is a very common problem for endurance runners as it is caused by ramping up mileage and overuse. Even easing into a long distance plan can cause the IT band to become inflamed. The pain is felt beside the knee or in the thigh and hip area and stems from a number of problems, including poor gait, weak hip abductors and/or over pronation.annotation This thick tendon can be a tough one to tackle due to its location and length, but the pain often subsides when a runner rests, performs stretches dedicated to the IT band, and uses a foam roller.

runner gripping knee ZOZI

runner gripping knee



Dr. Jon Mulholland, a sports chiropractor and certified strength and conditioning specialist who has treated dozens of Olympic athletes, says that when knee pain presents it is rarely an issue with the actual knee unless the knee has taken a direct hit. “If a runner comes into my office with IT band issues and the typical pain on the outside of the knee,” says Mulholland, “I rarely even look at the knee.”

Torn meniscus

The dreaded torn meniscus also causes knee pain or stiffness along with swelling. A severe tear may cause knee instability. It may also cause your knee to pop or lock up, making it difficult to straighten. A small tear could cause symptoms similar to ITB pain, making a minor tear difficult to self-diagnose. Rest can help in some instances, but if the tear is too bad, surgery may be required.    

So do you RICE it or take it in for an exam?

Your knee hurts. Your hamstrings scream. Have you simply overdone training and your body is requesting some rest, or have you injured something that requires medical attention and time spent away from your running shoes? 

“My rule of thumb with runners,” says Dr. Mulholland, “is that if their pain or discomfort is making them change their gait they shouldn’t be running.” Taking a few days off can be tough, but losing months of training due to a serious injury that wasn’t diagnosed early is worse. Mulholland says studies have shown running on an injury that causes a gait change (such as limping, shortening your stride, or favoring one leg over the other) just one or two times can alter your running gait permanently. This can cause additional problems, such as knee, hip, or achilles pain. In fact, running on one injury can easily lead to a second injury, making your return to running an even longer and more difficult feat.

In general, good pain occurs after a tough workout, lasts 24 to 72 hours, and happens in the muscles. Bad pain will last longer than 72 hours and can happen in the joints and tendons. If you feel pain in your joints or tendons and it lasts for more than a few days, find a medical doctor who specializes in sports injuries. Stay out of your running shoes until after the appointment; now is not the time to train like Meb. Instead, rest and ice, and, once a diagnosis has been made, follow the medical instructions given. And when the urge to run through the pain hits before your doctor says its safe to make a comeback, unlace those shoes, and remember this wise quote from ZOZI Guru Dean Karnazes: “Life is a series of obstacles and setbacks; living is overcoming them.”


The inward rolling of the foot when it hits the ground, which helps distribute the force of impact.

Kathy Murdock

Kathy works as a freelance writer and marketer from her home in sunny Florida. An avid runner, she has completed nine half marathons and two full marathons, along with a variety of other racing distances. She loves her family, long runs, hot coffee, and peanut butter.

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