Running Injuries: Prevention, Warning Signs and When to See a Pro

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It starts small. A twinge on the outside of the knee at mile four, gone by the shower. A heel that complains for the first few steps out of bed. A spot on the shin that hurts a little more each week. Most running injuries don’t arrive with a bang the way a tackle does; they creep in, and runners are famously good at ignoring them until the day they can’t. This page is about catching them early: the injuries runners get most, what tends to cause them, what lowers the risk, and the warning signs that mean “stop running and get it checked”. It’s for every runner, from the high school cross-country kid to the 60-year-old who runs every morning.

This page is general information, not medical advice. If you’re hurt, see a sports medicine doctor, physical therapist (PT) or certified athletic trainer (AT). For the bigger picture of the sport, start at our running hub.

How common are running injuries?

Common enough that most regular runners will meet one. A 2007 systematic review in the British Journal of Sports Medicine found yearly injury rates in distance runners ranging from 19.4% to 79.3%, with the knee the most frequently hurt. A larger 2022 review in the Journal of Athletic Training, pooling 36 studies and more than 23,000 runners, found about one in four runners injured overall: 14.9% of novices, 26.1% of recreational runners and 62.6% of competitive runners. The knee (25.8%), foot and ankle (24.4%) and lower leg (24.4%) were the most common sites. Per hour of running, novices get hurt more than twice as often (a 2015 meta-analysis): the body needs time to catch up with the lungs.

Two risk factors keep showing up: a previous injury and doing too much too soon. What “too much” means is covered on our running training page.

The most common running injuries

Runner’s knee (patellofemoral pain)

A dull ache around or behind the kneecap, often worse on stairs, squatting, downhills or after sitting with bent knees. The American Academy of Orthopaedic Surgeons (AAOS) says it’s common in sports, especially in women and young adults, and links it to repeated stress, a sudden change in activity, and weak or imbalanced thigh and hip muscles. The main approach in AAOS guidance and in the 2019 physical therapy clinical practice guideline on patellofemoral pain is exercise: strengthening the quadriceps and the hip muscles. That guideline does not recommend braces, sleeves or straps as a treatment, though some runners like how a sleeve feels (more in our knee brace for running guide). If the pain persists, see a PT or sports medicine doctor.

IT band syndrome

Pain on the outside of the knee that shows up at about the same point in every run and gets sharper on downhills. The American Academy of Family Physicians (AAFP) describes iliotibial band syndrome as a common knee injury in runners and cyclists, linked to high weekly mileage, lots of track running, interval training, and weakness in the thigh and hip abductor muscles. The AAFP review notes that most people improve within three to six weeks when they stick with their stretching and cut back on the running that provokes it.

Shin splints

Pain along the inner edge of the shinbone (medial tibial stress syndrome). AAOS ties it to a sudden increase in how often, how long or how hard you run, and says that if it doesn’t settle with rest, a doctor may look for a stress fracture.

Stress fractures and bone health

A stress fracture is a small crack that forms when bone breaks down faster than the body can rebuild it. AAOS says the weight-bearing bones of the foot and lower leg are most vulnerable, and that these injuries often appear 3 to 4 weeks after starting a new routine or season. Risk factors on its list: increasing activity too quickly, weak muscles that don’t absorb shock, hard surfaces, worn-out shoes, low bone density (more common in women), less than 7 hours of sleep or no rest days, not eating enough, and low vitamin D. The pattern to watch: pain that first shows up only after running, then during runs, then while walking, sometimes with swelling or aching at night. AAOS is blunt: don’t run through it; see your doctor.

Achilles tendinitis

Pain and stiffness in the cord at the back of the heel, typically worst in the morning and with activity. AAOS describes two types: noninsertional, in the middle of the tendon and more common in younger active people, and insertional, where the tendon meets the heel bone. Triggers include a sudden jump in amount or intensity of exercise, tight calves, and changes in shoes. Its prevention list: build up gradually, keep calves flexible, wear supportive shoes and cross-train with low-impact activities like cycling or swimming. A sudden pop in the back of the calf or heel is different: it can mean a rupture and needs a doctor right away.

Plantar fasciitis

The classic sign, says AAOS: heel pain with the first few steps out of bed, or after sitting a while, that eases as you walk. Runners get it from overuse; tight calves, age 40 to 60 and foot shape add to the risk. The encouraging part: AAOS reports that more than 90% of people improve within 10 months of starting simple treatment, such as rest and activity changes, stretching, supportive shoes and physical therapy. If it lasts for months despite self-care, see a doctor.

Heat illness: the emergency runners should know

In 2023 the Twin Cities Marathon was canceled on race morning for record October heat; in 2007 the Chicago Marathon was stopped mid-race as temperatures neared 88 °F and hundreds of runners needed care. Heat is a real risk at every level, even on mild days for a runner who pushes hard.

The American College of Sports Medicine (ACSM) 2023 expert consensus statement calls exertional heat stroke a true medical emergency: a core temperature usually above 40 °C (104 °F) with changes in the brain, such as confusion, odd behavior, stumbling, collapse or unconsciousness. The treatment is to cool first, transport second: whole-body cooling in ice water on site. At the Falmouth Road Race, ACSM reports, 274 runners in a row with heat stroke were cooled on site in ice-water tubs, with no deaths. Heat exhaustion (dizziness, nausea, weakness, heavy sweating, fast pulse) is less dangerous but means stop, get into shade and get help. The National Athletic Trainers’ Association (NATA) recommends acclimatizing to heat gradually over 7 to 14 days. How to race in the heat is on our race day page.

Two other race emergencies: hyponatremia (low blood sodium from overdrinking; see race day) and cardiac arrest, which is rare: 0.54 per 100,000 US marathon and half-marathon finishers in a 2025 JAMA study, with survival improving thanks to fast CPR and defibrillation. Chest pain, unusual breathlessness or fainting on a run means stop and get checked.

Female athletes, men too: RED-S and bone health

When runners don’t eat enough for the training they do, the body cuts back. The International Olympic Committee (IOC) 2023 consensus statement calls this Relative Energy Deficiency in Sport (REDs): low energy availability that can affect hormones, bones, the heart, mood and performance, in women and men. It grew out of the “female athlete triad” and matters in running, where lighter can look faster. In a study of 156 male collegiate distance runners, 27% had a bone stress injury over about two years, and runners with more risk factors (low energy availability, low body weight, low bone density, earlier bone injuries) had more of them.

Warning signs to take to a doctor: missed or stopped periods, repeated stress fractures, constant fatigue, dropping performance despite training, frequent illness, or strict food rules. A sports medicine doctor and a registered sports dietitian are the right team. Our running nutrition page covers eating enough.

What lowers the risk

• Build gradually, especially the long run. A 2025 study of more than 5,200 runners with Garmin data found that a single run more than 10% longer than your longest run in the past 30 days raised the rate of overuse injury. Details on the training page.
• Strength train. A 2018 meta-analysis found strength programs cut sports injuries to about a third. Think calves, hips, quads and hamstrings.
• Rest and sleep. AAOS links stress fractures to under 7 hours of sleep and no rest days. See our running recovery page.
• Eat enough, with calcium and vitamin D in your diet (AAOS), and carbs to match training.
• Replace worn shoes and mix in softer surfaces (AAOS), changing one thing at a time.
• Try small form tweaks if you’re prone to knee pain. A slightly quicker step rate lowers load at the knee in lab studies; see our running form tips.

Gear many runners use

No product prevents or treats an injury on its own; ask your PT what fits you. Many runners keep a knee sleeve like the Bauerfeind GenuTrain or a strap below the kneecap like the Cho-Pat Original Knee Strap for comfort on longer runs, a foam roller like the TriggerPoint GRID for warm-ups and calves, and a supportive slide like the OOFOS OOahh instead of walking barefoot after a run. More in our knee sleeves and recovery shoes guides.

When to see a sports medicine doctor, PT or athletic trainer

• Call 911 / emergency: a runner who collapses, is confused or acts strangely in the heat (cool them in ice water if trained help is there), chest pain or fainting, or a sudden pop in the Achilles with trouble walking.
• Within a few days: pain in one spot on a bone, pain that hurts when you walk or at night, swelling, or a limp.
• Soon: pain that keeps coming back at the same point in your runs, heel pain that hasn’t improved after a few weeks of easing off, missed periods, or a second stress fracture.

A sports medicine physician diagnoses and orders imaging; a physical therapist builds the strength and return-to-run plan; an athletic trainer is often the first contact at high schools and colleges. Return usually moves from walking to run-walk to easy running, then longer and faster, as long as each step is pain-free; cross-training keeps your fitness meanwhile. Play soccer too? See soccer injuries.

Running injuries: FAQs

What is the most common running injury?

The knee is the most commonly injured area in runners, and runner’s knee (patellofemoral pain) is a big part of that. In a 2022 review of more than 23,000 runners, the knee accounted for about a quarter of injuries, with the foot and ankle and the lower leg close behind.

How do I tell shin splints from a stress fracture?

You can’t be sure on your own. Shin splints tend to hurt along a longer stretch of the inner shin; pain in one small spot on the bone, pain while walking or at night, or swelling point more toward a stress fracture. AAOS says: don’t run through it; see a doctor.

Can I keep running with IT band pain?

Back off the running that brings it on (often downhills, the track and long runs) and work on hip strength and flexibility; the AAFP review says most runners improve within three to six weeks. Pain that changes how you run means stop and see a PT.

Do knee braces help runner’s knee?

The 2019 clinical practice guideline for patellofemoral pain does not recommend braces, sleeves or straps as treatment; exercise for the hips and thighs is the core. Some runners still like a sleeve for comfort. Ask your PT, and see our knee brace for running guide.

Is it normal for a female runner to miss periods?

No. Missed or stopped periods can be a sign of low energy availability (REDs), which the IOC links to bone loss and stress fractures. See a doctor, ideally with a sports dietitian; it’s not a badge of hard training.

What are the signs of heat stroke in a runner?

Confusion, strange behavior, stumbling or collapse during or right after a hot run, with a very high body temperature. ACSM calls it a medical emergency: call for help and cool the runner immediately, ideally in ice water, before transport.