Despite what runners read & hear every day, studies have yet to discover what causes most running related injuries (RRIs). Well actually that’s not entirely true the thing that causes most running related injuries is surprise surprise… RUNNING!
So now we have got that one out of the way what other factors may also be involved?
A recent study by Saragiotto (2014) asked runners what they thought contributed to injuries in runners. The most common answers were:
• Not stretching
• Wearing the wrong shoes
• Foot-type changes
• Excess of training
• Not warming up
• Lack of strength
• Not respecting the body’s limitations
So time to examine what evidence there is for some of these commonly held beliefs.
Not stretching, a recent systematic review by Lauersen et al (2013) found no evidence to support stretching before or after sport to reduce injury risk. An earlier study by Wilson (2010) actually found that stretching may decrease endurance performance & increase the energy cost of running.
A good example of this is Paula Radcliffe who in 2003 set the still unbeaten world record for the women’s marathon record of 2:14:25. As part of her training for this she saw her sit and reach test decrease by 4cm. This was in part due to a specialised strength and conditioning program that also saw her maximum vertical jump test increase by 10cm giving her increased power in her stride
Wearing the wrong shoes, over pronation is not a diagnosis. It seems likely that marketing from shoe companies labelling pronation as harmful and providing a solution (in the shape of an expensive shoe) is to blame for this widely held belief. A systematic review by Richards (2009) titled “Is your prescription of distance running shoes evidence-based?” concluded that there was no evidence base for the prescription of running shoes for distance runners. A more recent study by Malisoux et al (2013) found that using a variety of different running shoes may help to reduce running injuries by helping to vary loading patterns. Antoher study be Nielsen et al (2014) found that foot pronation was not associated with injury risk.
A good example is Haile Gebrselassie the legend is an over pronator. He won two Olympic gold medals over 10,000 metres and four World Championship titles in the event and set 27 world records, and is widely considered the greatest distance runner in history. …Geb races in Adidas Adizero Adios.
Another commonly held belief is that heel striking is bad and the root of all evil and that forefoot or mid foot striking is the answer to all running injury woes. This belief became popular following the rise of the famous “Born to run” book. Again when we examine the evidence this does not stand up to scrutiny, Larson (2010) examined foot strike patterns in recreational marathon runners during the 2009 Manchester city marathon. They found that the majority 88.9% of runners at 10km heel striked only 3.4% landed on their forefoot. By 32km the percentage heel striking had increased to 93%.
Not all heel strikes are equal as shown in a recent study by Davis et al (2015) where the researchers found that those runners who landed with less impact force had reduced rates of injury and many of these were heel strikers. What may be more important is whether you land with a slightly flexed or a straighter knee and how far four foot lands in front of your hips. Generally a small increase (5-10%) in your step cadence (the number of steps you take per minute) can help to reduce impact loading and has been shown to help reduce impact loading and may help reduce running related injuries (Heiderscheit 2011).
Excess of training, now were getting somewhere. Estimates suggest 60-70% of running injury is due to training error but some papers suggest it may be as much as 80%. Overuse injury occurs when load exceeds tissue capacity, if time for adaptation is too short or volume of running too high, an overuse injury can occur. The major causes of most overuse RRIs are due to training errors.
Not warming up, warming up has shown some evidence of reducing injury risk in some sports, there is little evidence to suggest it significantly reduces risk of running injury.
Lack of strength, again some research from non-running sports suggest strength training can reduce sports injuries to less than a 1/3 and reduce overuse injuries by almost 50% Lauersen (2013).
Not respecting the body’s limitations, now we have to remember that we are all individuals and what may constitute a normal running load for a highly trained elite athlete may be completely unachievable for the average recreational fell or marathon runner. A higher body mass index (BMI>25) has also been linked to an increase risk of injury as has a previous history of injury especially in the last 12 months (Malisoux et al. 2014, Saragiotto et al. 2014b).
An analogy from a previous lecturer that epitomises this is that of donkey from the film Shrek. Donkey dreams of being a noble steed much like many of us might dream we are the next Paula Radcliffe or Mo Farah but what donkey needs to remember is that he is not a noble steed he’s a donkey and if he tries to train and run like a noble steed he’s probably going to end up lame and looking like an ass.
In summary, the main causes of running related injuries that are backed by the research literature are training errors, a high BMI and a previous history of injury. Things that can help to reduce injury risk are improving lower limb muscular strength, improving co-ordination and proprioception and trying to run with less impact either by landing with a slightly flexed knee or trying to increase your running cadence.
Information for this blog was gathered from an article by Tom Goon the running physio he’s on twitter @tomgoon and check out his blog at https://www.running-physio.com/
and from a presentation at Therapy Expo from Matt Phillips again you can find him on twitter @sportinjurymatt or check out his blog at https://www.sportinjurymatt.co.uk/
Both sites have some excellent evidence based running injury advice and articles
