In previous articles, we’ve looked at the usefulness of specific treatments for running injuries, like ice baths, heat, and kinesiology tape. But something we haven’t spent much time on is overall theories of injuries—how they develop, why they hurt, and how we might go about recovering from them.
Today, we are tackling the model of inflammation as a primary cause and foe in running injuries.
What is the role of inflammation in running injuries?
For a long time, inflammation has been identified as the main culprit for pain resulting from running injuries.
The inflammatory theory of running injuries asserts that, following minor damage from overuse to a muscle, tendon, or connective tissue, the body attacks the injured area with a rush of inflammatory cells which results in the pain, stiffness, and soreness at the injured site.
This inflammation has a detrimental effect on healing because the swelling and inflammation can cause secondary damage to the already-injured area.
To combat this, many treatments that have become mainstays of physical therapy offices and athletic training rooms are designed around reducing inflammation. This includes ice, anti-inflammatory drugs like ibuprofen, and compressive wraps.
But is this inflammatory model valid?
By definition, inflammation has features that are observable both on the macroscopic level of sensations in your body (like pain, redness, swelling—things a doctor would call “clinical features”), and on the microscopic level of the inner workings of your cells—this consists mainly of special inflammatory cells which flood an inflamed area and mediate your body’s response to the injury.
If the cause of the pain or irritation at the site of an injury truly is inflammatory in nature, both the macroscopic and microscopic signs should be evident – but microscopic signs aren’t easily detectable.
Sensations like pain, redness, and swelling are easy to observe, but you need to actually look at tissue under a microscope or with high-tech biology equipment to see the cellular markers of inflammation.
As you might guess, runners and other athletes with mild or moderate overuse injuries aren’t too keen on letting researchers put a slice of their Achilles tendon or plantar fascia under a microscope in the name of science.
Partly because of the difficulty of observing the cellular signs of inflammation, the inflammatory theory of running injuries has been popular for quite a while. Problems with it have arisen only recently, as doctors and researchers have begun to thoroughly investigate the root causes of overuse injuries.
Treatments and rehabilitation vs inflammatory model
Using tissue samples taken from patients with chronic tendon or plantar fascia injuries who undergo surgery (and are hence being sliced open anyhow), recent studies have demonstrated a lack of inflammatory markers at the cellular level. Instead, what they observe in injured tissue under a microscope is profound damage and degeneration in the microscopic structure of the tissue.
- Other research has highlighted the relatively poor track record of anti-inflammatory treatments like non-steroidal anti-inflammatory drugs and corticosteroid injections. And the most promising emerging treatments for soft-tissue overuse injuries don’t appear to address inflammation at all.
- The eccentric heel drop exercise developed for Achilles tendonitis and the decline squat exercise developed for patellar tendonitis both focus instead on attempting to fix the structure of the tendon through controlled eccentric stress, and the most successful rehab programs for knee injuries like IT band syndrome and patellofemoral pain syndrome (runner’s knee) are focused on improving hip strength and coordination to reduce damaging stresses on the knee from poor running mechanics. In essence, as our very own Matt Phillips pointed out, we need to think prehab rather than rehab!
- More intensive emerging treatments like shockwave therapy or nitroglycerin patches don’t focus on reducing inflammation either—in fact, often the goal is to induce controlled inflammation or increase bloodflow, targets anathema to an inflammatory model of injury. This is in keeping with the fact that some researchers believe that inflammation is a helpful and necessary component of recovery.
Final notes and specific recommendations for rehabbing your injuries
So, knowing that the inflammatory model of injury is unsatisfactory, how does this inform the way we think about treating and rehabbing injuries?
- First, it should give us pause when evaluating any new treatment, therapy, or device which claims to reduce inflammation.
- Second, we should also acknowledge that many (if not all!) injuries are painful because there is real, physical damage to something in your body.
- Instead of icing a bit or taking some ibuprofen before you run, your recovery plan should be more cautious and allow your body time to repair the damaged tissue.
- While this might include taking time off from running, it might also be simply modifying your running schedule to put less stress on an injured area.
- Finally, it means that you should concentrate your rehabilitation efforts on the treatments that are most likely to help with your particular injury (typically specific strength exercises and sometimes stretches) and put less emphasis on traditional anti-inflammation tactics like icing, anti-inflammatory drugs, compression wraps, and elevation.
Though we need scientific research on individual treatments to explicitly rule out specific treatments for specific injuries—for instance, the absence of inflammation in connective tissue injuries doesn’t necessarily mean we should throw out the notion that icing, for example, can be useful—an overall model of understanding the biology that underpins an overuse injury can help you prioritize your recovery plan.
5 Responses
Cold is important because even though the visible swelling may be down, there may be internal inflammation still present. When inflammation is present, your circulation is prohibited and can’t do the healing it needs to. This is why it is always best to do a cold treatment after any activity (once you have healed enough to get back on your feet). I think that cold therapy is very important but for only a period of time. In order to help heal soft tissue injuries, you need blood flow. I highly recommend a treatment called BFST (blood flow stimulation therapy). I know and talk to a lot of people this has worked for. http://www.kingbrand.com/Plantar_Fasciitis_Treatment.php?REF=46PV1
Interesting Maizie, thank you for your input. Some of our readers will be very interested to learn more about it, other readers have talked about it as an alternative to ultrasound in this post https://runnersconnect.net/running-injury-prevention/can-ultrasound-treat-overuse-running-injuries/. Glad you four something that worked for you!
Hi Coach Tina 🙂 I just read that ultrasound article. I am surprised that they didn’t at all talk about the increased blood flow devices like that and the BFST stimulate in order to heal. They mentioned ‘hot packs’ in the article and as much as heat does relax the muscles, in order to heal, heat must be promoted from below the dermal layer. Heat on your skin simply draws the blood flow to the surface, you need to promote it deeper down, within the injured soft tissue. Thanks for linking that article for me to read 🙂 I’m gonna post this on there too I think.
I had never heard of it before, but it does sound interesting, and I have added it to our list of posts to cover. Thanks for reporting back, and hope you enjoyed the other article! I am sure your input will help others!
Just came across this post while doing a literature review on long-term effects of inflammation after an acute injury for a pain medicine research fellowship at UC San Diego. I agree that there is definitely a lack of research on this specific topic. But in response to Maize, ice actually does the opposite of the intended effect you report. Ice will cause the blood vessels to constrict, thereby reducing blood flow to the area, which decreases the transport of pro-inflammatory and anti-inflammatory mediators to the area. It’s not the inflammation that reduces circulation, but the cold therapy itself. Inflammation actually promotes circulation by signaling other cells to come to the area and assist with healing.