This article was written by Sean Rimmer, PT, DPT, OCS, and first appeared in ATRA’s spring 2023 quarterly newsletter. Sean is an avid trail runner and physical therapist living in Colorado Springs, CO, where he is the owner at Run Potential which focuses on rehab and performance training for runners.
If you happen to be reading this article, you likely enjoy the activity of running. Whether you run for stress relief, socially with friends, competitively, or anywhere in between, the act of running often brings more to life than just running itself. On the contrary, if unable to run due to pain, we often lose all of the physical, mental, and emotional benefits we gain from the aspects of running we enjoy. So, what kind of pain should cause us to stop running and is it okay to keep running through some pain? Unfortunately, the answers can be both simple and complex.
What is pain and why does it matter? These questions will be addressed in this article, related to the concept of pain, the specific sites of pain from running, when it may be okay to run with some pain, and when to pull the plug from running.
Why we Perceive Pain
When we think of pain onset, we often perceive it as a peripheral sensation from the local tissue involved due to tissue damage or trauma. For example, if you’re out for a trail run and you catch your toe on a tree root causing you to fall directly on your knee, oftentimes your knee will become slightly swollen and will likely begin to hurt. Though it may appear that pain is a peripheral signal from the irritated knee during the fall, if I were to give the same example of a trail runner falling on their knee while being chased by a mountain lion, the perception of pain would most likely not be the same. In fact, you may not feel pain at all! This is likely because the knee irritation from the fall is ultimately less of a perceived threat than the individual being attacked by the mountain lion. The deciding factor of pain perception in this case comes down to your brain. Your brain has the power to override the pain signal from your knee to allow you to keep running to improve your chance of survival. Therefore, we can come to a conclusion that pain likely has both peripheral (from the local tissue) and central (from the brain) pathways that can feed into our perception of pain.
Our perception of pain can also be modulated by our past experiences or our emotional states, and interestingly enough, there may be no true tissue damage. Again, it comes down to what our brain perceives as a threat. For example, if you have a history of anterior (patellofemoral) knee pain from running technical downhills, and you take time off from running downhills, you may still perceive some pain sensitivity during technical downhill running in the future. This is because our brain remembers the initial stimulus during the onset of pain. Even if our irritated knee tissue heals and we have no pain running uphills or flats, there still is a chance that our brain may be threatened when we return to the downhills again even if there is no true knee tissue damage.
Andy Wacker Races Downhill. Photo: Robert Urbaniak
Pain can be used as a guide, or a response that our brain wants us to do something differently. In fact, this could be because we have true tissue damage and we need to recover. For example, if we have foot pain when running, but not when walking, this may mean our brain is interpreting the higher loading of running to be threatening or damaging to our foot, but not so the lower threshold activity of walking. This is ultimately a good response, as pain can act as a guide to allow proper tissue recovery. If we didn’t have a pain response, we would have no buffer to which activity or movements would be harmful to our body. This is something to remember the next time you go reaching for the bottle of anti-inflammatory pain medication after your foot starts hurting after a run. With that being said, should we really mask our pain response? The answer is no!
Pain from Running
Now that we can appreciate that pain can be modulated by the brain for a variety of reasons, it’s important to understand when it’s okay if we run with some pain, and when we should not run until we are pain free. When it comes to running-related pain, we must consider the tissues involved such as bone, tendon, muscle, ligaments, cartilage, etc. The reason why it’s important to understand which tissue is involved is because running with mild to moderate pain related to certain soft tissues – like muscles and tendons – may be okay as further damage may not occur, but when dealing with bone-related pain, continuing to run could potentially cause longer term damage if the bones do not have the appropriate amount of off-loading. If you’re unclear which tissue is involved, understand where the pain is located, which movements cause pain, how the pain came on, and how pain responds to running. All of these clues can give insight as to which tissue is involved, but further consultation with a skilled medical provider or physical therapist to diagnose the injury may be the best path to optimal recovery.
Common Tissues Subjected to Pain while Running
Unless you have a trauma resulting from a fall while running, oftentimes pain onset is due to repetitive microtrauma in bones or tendons, as these tissues tend to have a higher susceptibility to running-related pain or injury.
Common tendon pain seen in runners can occur within the following tendons (but not limited to): The Achilles tendon, posterior tibial tendon, peroneal tendon, patellar tendon, quadricep tendon, glute medius tendon, and proximal hamstring tendon. Note that plantar fascia and iliotibial band (ITB), also act like tendons which store and release energy during a run, and can also be a common site of “tendon-like” pain. Typically tendons can become painful if they lack tissue capacity for specific training, if they are being overused due to a compensation pattern, or if lacking control/strength within the region of the tendon crossing the joint(s).
There are some key patterns to help identify if a tendon is the tissue involved in your pain while running. First consider the area of irritation. If the irritated area is local to a tendon and you can press or squeeze the tendon specifically to identify that it’s irritated, then likely the tendon is the source of your pain. This is easier to identify at more superficial tendon sites like the Achilles and patellar tendon, however, this may be more difficult to appreciate at deeper tendons like the glute medius and proximal hamstring that attach to the pelvis.
Tendons do typically present stiffer or are irritated after longer periods of rest (sitting or sleeping), and most notable after the first few steps if you have been sitting or resting for a while. Tendons also tend to warm up with running. Even though tendons may feel stiff or irritated in the beginning of a run, they start to feel better during the run, or often no worse. If a tendon is irritated, it will often feel worse with overloading the tendon during the joint motion which causes lengthening. For instance, your achilles tendon may become more irritated during loaded dorsiflexion, or your patellar tendon may become more irritated during loaded knee flexion.
Bone-related pain from running may be due to a bone stress reaction, a stress fracture, or a full fracture. Typically bone pain can be either dull, achy, or sharp depending on the degree of stress, and depending on the activity stressing the tissue (ie. standing, walking, running, etc). Some common sites of bone stress reactions can occur in the following areas in runners: metatarsals of feet, navicular of foot, calcaneus of foot, anterior or posterior tibia, femoral shaft, femoral neck, and sacrum. Bone stress sites can also be defined as high risk, medium risk, or low risk by the location which is indicative of the bone’s ability to heal in an optimal environment. High risk sites, like the femoral neck, are at risk for poor healing due to a poor blood supply and a higher load-bearing region.
Bone-related pain can be both simple and challenging to identify. Similar to tendons, if bone is superficial and it’s tender to the touch in a focal region, there is potential that the bone is the site of pain. Bone-related pain also tends to feel worse with repetitive loading over time and does not warm up like tendons or other soft tissues. For example, when dealing with bone-related pain, you may have mild pain starting your run, but where pain worsens during the run. Bone-related pain, if progressing, could reduce the ability to tolerate walking, or even standing. It’s imperative to identify bone-related pain as early as possible because continuing to run with bone-related pain, can lead to a longer recovery and ultimately poor bone healing. As runners, we need our bones to be strong so we can continue to progress our running volume and intensity over time.
When dealing with running-related pain, I often use a traffic light analogy as a guide to understand when running with pain may be okay, and when we should hold off on running and seek medical advice. To a point, this guide does take into account which tissues may be involved based on the subjective and objective points listed below. By no means is this guide perfect, as pain can be complex, but this can provide insight into the severity of tissue irritation, the location of tissue damage, and even where tissue may be in the stage of healing.
A Traffic Light Analogy to Guide:
Red Light: Stop running and seek medical advice.
Yellow Light: Continue to run with caution. It may be beneficial to seek medical advice to prevent progression of pain or symptoms.
Green Light: Likely you have mild pain, but will do no harm continuing to run. You can likely reduce your running volume, frequency, or intensity to reduce tissue stress.
Red Light:
If pain progressively worsens during a run.
If pain alters your running form/mechanics.
If pain lingers for >24 hours post run
If pain progresses from running to walking, then even resting/non-weight bearing activities.
If pain is local to a bone, and if the bone is tender to the touch and worse after running.
Yellow Light:
If pain is less than a 5/10 perceived intensity and improves or does not worsen during the run.
If pain lingers briefly after your run, but improves back to baseline throughout the day.
If pain is specific to a soft tissue/tendon, and not a bone.
Green Light:
If pain remains <3/10 perceived pain intensity while running, and or “warms up” during your run to feel better.
If you have <3/10 perceived pain intensity while running which does not worsen during or after your run, and you have no pain with day-to-day activity.
Pain not in the site of palpable bone.
Summary
Remember, pain can be both simple and complex. Pain likely has peripheral and central inputs from our nervous system, but is ultimately decided on by the brain based on its perceived threat. Pain intensity can be modulated by our past experiences, emotional state, or even stress, and pain can best act as a guide. Don’t mask pain with medications, rather make a change in what you are currently doing to reduce the painful input. This could mean less running, adding resistance training, altering running terrain, and the list goes on.
My message: pay attention to your pain. Use the traffic light analogy as a guide, and seek help if you’re struggling to improve. The worst case scenario is continuing to run with progressively worsening pain, and/or masking pain with medications etc. You could potentially do longer term damage to your body. Ultimately, this could mean you can’t run, and if you can’t run, you lose the ability to enjoy running for all of the [fill in the blank] reasons.
Recent articles from Sean Rimmer include: Foot and Ankle Health for Trail Runners and How to Prepare your Legs for Mountain Trails.
