Which different running biomechanic styles cause running injuries and how do we treat them?
One of the most common beliefs in the running world (including field/court-based sports) is that particular running styles cause certain injuries. The way we run is often referred to our running biomechanics. However, does this continued long held belief actually have any truth to it? Well, this belief is somewhat true. If you have already read my previous blog ‘How common are running-related injuries and who is affected the most?’ you will already know that running biomechanics only determines where the injury will manifest itself. Furthermore, you will already understand that it is a training load error that essentially causes all running-related injuries. To avoid a training load error, it is crucial you gradually build up an overall tissue load capacity in the gym and when running. So in a quick summary, if you avoid a training load error it is unlikely you will ever sustain a running related injury, and therefore your biomechanics do not matter.
What if there is a training load error and you are now injured or in pain? Firstly, you should book in to see your osteopath or other health professional who is experienced in the management of running injuries. They will help you determine what was the training load error and what other factors contributed to this training load error. Now if they are any good at their job, they will not go all in on your running biomechanics. They firstly will look or discuss your running program to understand where it may have gone wrong. Secondly, they will look and discuss your gym program. Yes, strength, power, speed and plyometric training is a fundamental component of injury prevention and improving performance for all runners. If you are not already completing regular and appropriately programmed strength and conditioning, it is highly recommended that you begin. Lastly, they may look at how you run. However, in all honestly most of the time it is a complete waste of your time as it only tells us where the injury will occur. With you being in pain, we already know where the injury is! Furthermore, based off where the injury is located a good practitioner will have a good idea of where your foot is striking and if you overstride.
Do I ever suggest changing biomechanics if you are injured to offload the injured site? Sometimes I do, although these suggestions are encouraged for symptom modification in the short term whilst we are treating the training load error in combination with poor tissue quality. Experienced health professionals understand what running style can offload the forces to the injured site. However, by doing this it is important to note we are then changing the loading to another site making it at risk of injury. This is why the importance of what we do must not be focused on biomechanics, it must be focused on improving your load capacity through improving your overall tissue quality to withstand forces.
Which running styles result in the pain being manifested at the specific location?
Firstly, it is important to know that treadmill running and overground running produce no difference in ground reaction forces. Vertical, braking and propulsive ground reaction forces are essentially equal according to the research when comparing the two different running surfaces. However, achilles tendon forces are slightly higher when treadmill running compared to overground running (Willy et al., 2016). My clinical advice for those with an achilles tendinopathy who want to treadmill run is to slowly and progressively build up load capacity with overground running first.
The most common question when it comes to fears of biomechanics is “Where should my foot strike?” It depends on you as an individual on what your natural running style is. There is absolutely no evidence that shows one strike pattern is better than the other. Approximately 80% of runners are heel strikers. Heel strikers land on the outside of the heel and absorb more force at the knee. Whereas, forefoot strikers land on the outside of the forefoot and absorb more energy at the ankle. Essentially changing the way your foot strikes just transfers the load to another major joint and the musculoskeletal tissues around it.
There are two major running styles biomechanically that people will have. The first is known as a proximal mechanism of running and the other is overstriding. A proximal mechanism runner is someone who runs with their thighs close together. Essentially, they will have a hip drop, and an adducted internally rotated thigh. These individuals commonly will experience patellofemoral pain (knee pain) and medial tibial stress syndrome (shin splints)/ tibial stress fractures. Someone who overstrides is quite easy to identify and relatively easy to modify their biomechanics if needed. I normally will address this style by suggesting reducing step length and increase your cadence (steps per minute). Increasing cadence has time again been shown to be an effective way to reduce overall ground reaction forces and also is beneficial to performance. The higher the cadence, the more economical runner you are. Overstriding increases strain/force through the ITB, knee, plantar fascia, tibia and hamstrings.
What are strategies to treating running injuries?
Remember that our essential treatment goal is to restore and then improve load capacity. We do this by smart running programming and actually being in the gym improving our tissues overall quality to withstand ground reaction forces and strain. By improving the load capacity, we are increasing the threshold before a training load error can occur.
What muscles should we train? Research by Dorn et al,. 2012 found that the different muscles of the lower limb produce different forces to achieve the task of running. The gluteus maximus produces 1.5-2.8 body weights of force, whilst the stabilising gluteus medius produced 2.6-3.5 body weights of force. At the knee, the quadriceps was found to produce 4-6 bodyweights of force. However, the ankle joint was shown to contribute to the forces of running the most with the gastrocnemius of the calf producing 2.5-3 bodyweights of force. Whilst the king and powerhouse of the runner, the soleus muscle in the lower calf produces a whopping 6.5-8 bodyweights of force. So many people neglect their calves, however they should be a fundamental target of your training in the gym.
You need to be lifting heavy weights in the gym! As shown the soleus in particular needs heavy loads to transfer over to its function during running. Lifting heavy weights in general is one of the best ways to maximise the neuromuscular system. With smart strength programming we can improve your tissue qualities dramatically. Lifting heavy weights more than 70% of your maximal voluntary contraction is essential to develop tendon stiffness (Bohm et,. 2015). This improved stiffness transfers over into you being more elastic in your running and reducing ground contact times.
Plyometrics train our stretch shortening cycle and improve tendon stiffness and ground contact times. Plyometrics are also a fantastic way to improve the quality of our skeleton making it more robust and resilient. Plyometrics are great throughout rehab as they work on the rate of energy storage and release with higher peak loads. It does this without suffering the accumulation of loads during running.
I spoke about increasing cadence earlier and its positive effects on reducing overall ground reaction forces when running. As little as a 5-10% increase in cadence reduces patellofemoral joint loads by 15-20%, tibiofemoral contact forces by 7.5-11%, 9-11% lower gluteus medius and maximus demand, 3.6% lower achilles tendon force, 10% reduction in plantar fascia loads and an overall 18-22% reduction in vertical ground reaction force load rates. Cadence is probably the only biomechanical consideration I strongly advocate for, the evidence absolutely stacks up!
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