Running Injuries: Why Runners Get Hurt and How to Reduce Your Risk
Written by Dr. Josh Funk, DPT
Most running injuries are not caused by bad luck, the wrong shoes, or skipping a stretch. They are caused by load: asking your body to absorb more than it has been built to handle. A 2021 systematic review in the Journal of Sport and Health Science found roughly 40 percent of runners in prospective studies sustained a running-related injury, most often at the knee, ankle, and lower leg. The most consistent risk factor across the research is a previous injury. The good news: load is something you can manage, and capacity is something you can build. Here’s how.
This article is general education, not a diagnosis or treatment plan. If you have pain that changes how you run, worsens as you run, or doesn’t settle with rest, see a licensed physical therapist or physician.
Why runners actually get hurt
Running is repetitive by design. Every mile is roughly 1,500 steps, around 750 landings on each leg, and each one sends force up through the foot, ankle, shin, knee, hip, and trunk. Tissue adapts to that stress and gets stronger, as long as it gets enough time and enough capacity to keep up. Injury happens when load climbs faster than the body adapts.
Load can spike in obvious ways (adding a long run, jumping mileage before a race, a new hill workout) and less obvious ones (a training block after time off, a new surface or shoe, life stress that cuts into sleep and recovery). A Danish study of 874 novice runners, published in JOSPT in 2014, found runners who increased weekly distance by more than 30 percent over two weeks appeared more vulnerable to distance-related injuries than runners who progressed by less than 10 percent.
The other side of the equation is capacity. Weakness or poor control anywhere in the chain, from the foot and calf through the quads, hips, and trunk, means less margin for the same mileage. So does a previous injury that was never fully rebuilt. Two runners can follow the same plan and get very different results: the plan is the same, the bodies running it are not.
The injuries runners see most
Runner’s knee. Pain around or behind the kneecap (patellofemoral pain), often worse on stairs, hills, or after sitting. One of the most common running injuries, and one of the most responsive to the right strength work. I break down why it happens in Why Does My Knee Hurt When I Run? If the pain sits on the outside of the knee instead, it may be IT band syndrome, a different problem with a different fix.
Shin splints and bone stress injuries. A dull ache along the inside of the shinbone (medial tibial stress syndrome) is common in newer runners and anyone ramping mileage fast. Our shin splints guide covers causes and what to do. Pain that turns sharp and pinpoint on the bone is a different problem, a possible bone stress injury, and needs evaluation before more running.
Achilles tendinopathy. Pain and stiffness in the tendon at the back of the ankle, often worst first thing in the morning. A tendon problem is a loading problem, and the fix is loading it correctly, not resting it indefinitely.
Soreness vs. injury. After a hard week or a race, some soreness is expected. Some pain is your body flagging a problem. Our guide to sore vs. injured running covers how to tell the difference.
What actually reduces your risk
Progress training load gradually. Big jumps in weekly distance are a well-documented warning sign. The popular “10 percent rule” is a reasonable starting point, but the research doesn’t support one magic number. What matters is that load builds steadily and that you respect the weeks after a break, an injury, or a race. More in How to Increase Running Volume Safely.
Strength train. A 2014 meta-analysis of 25 randomized controlled trials in the British Journal of Sports Medicine found strength training reduced sports injuries to less than one third, and overuse injuries could be almost halved. Stretching, in the same analysis, showed no meaningful effect. For runners, that means single-leg squats, split squats, step-ups, heavy calf raises, hip bridges, and, as capacity builds, plyometrics like hops and bounds. It’s the part of training most runners skip and the part with the strongest evidence behind it. More in Why Strength Training Is Non-Negotiable for Runners.
Treat a past injury as a reason to rebuild, not just recover. A 2015 systematic review in PLOS ONE found strong evidence that a history of previous injury is associated with a higher risk of a new running injury. That’s not a sentence, it’s information: the injured area needs its strength and capacity measured and restored before mileage climbs again.
Don’t let pain-free be the finish line. Pain going away tells you tissue has calmed down. It doesn’t tell you the calf, quad, or hip has the strength to handle race-week mileage. Those are separate questions, and only one of them is answered by how you feel. It’s the same principle behind criteria-based return to sport.
How Rehab 2 Perform builds a plan for runners
We treat running injuries the way we treat every return to performance: Assess, Don’t Guess. Using HUMAC NORM isokinetic dynamometry (machine-measured strength at controlled speeds) and VALD force plates (which measure how much force you produce and absorb, and how evenly each leg does it), we measure where your capacity actually stands, side to side and against the demands of your mileage. Running Analysis adds how you move at speed.
From there, we build Movement Health around the gap:
- Competency: single-leg control and movement quality, because running is a series of single-leg landings.
- Capacity: the strength of the calf, quads, hips, and trunk to absorb load mile after mile, built with progressive strength work and measured, not assumed.
- Conditioning: a graduated return to mileage and intensity that matches what testing shows your body can handle, so training builds instead of breaks down.
The goal isn’t just getting you back to running. It’s getting you back stronger, with more margin than you had before. That’s Ready 2 Perform, and it’s why runners trust a team with 16 locations across the DMV, an NPS of 94, and more than 2,700 five-star Google reviews.
Frequently Asked Questions
Runner’s knee (patellofemoral pain), Achilles tendinopathy, shin splints (medial tibial stress syndrome), IT band syndrome, and plantar fasciitis are among the most common. A 2021 systematic review found the knee, ankle, and lower leg account for the largest share of running injuries.
Why do runners get injured?
Most running injuries happen when training load increases faster than the body can adapt. Sudden jumps in mileage or intensity, returning after time off, limited strength through the legs and hips, and a previous injury that wasn’t fully rebuilt are the most common contributors.
Mild soreness that stays mild during the run, doesn’t change how you run, and is back to baseline by the next morning is usually part of training. Pain that is sharp, localized to one spot, gets worse as you run, changes how you run, or lingers after rest is worth getting evaluated before you keep building mileage.
There is no single proven number. The 10 percent rule is a reasonable guideline, and research on novice runners suggests jumps of more than 30 percent over two weeks are associated with more distance-related injuries. Progress steadily, and be more conservative after a break, an injury, or a race.
Strength training is one of the best-supported ways to reduce sports injury risk. A 2014 meta-analysis found it reduced sports injuries to less than one third and nearly halved overuse injuries. For runners, that means single-leg strength, calf work, and hip and trunk strength, progressed over time.
In Maryland and Virginia, no. Direct access laws let you book a physical therapy evaluation without a physician’s referral.
Running into the same problem every training block?
Find out where your margin is now, while you’re healthy. Book an evaluation at one of our 16 DMV locations. We’ll measure your strength and capacity, look at how you run, and build the plan that gets you to the start line, and the finish, with more to spare. No referral needed in Maryland or Virginia.
About the author: Dr. Josh Funk, DPT, is the founder and CEO of Rehab 2 Perform. He captained Ohio State’s Division I men’s lacrosse team, played professionally in the National Lacrosse League, and earned his Doctor of Physical Therapy from the University of Maryland.