Injury prevention: time to self assess?

There are good reasons why running is such a popular sport; it produces high levels of aerobic fitness in a time-efficient manner, it can be done anytime, anywhere, and it only requires a minimal outlay for equipment (just decent shoes needed). However, there is a downside for runners, especially who train and compete recreationally or at the amateur level, and that is the risk of picking up a running-related injury (RRI).

Data accumulated over a 15-year period shows that in any 12-month period, lower extremity RRIs occur in an estimated 50% or so of recreational runners, with some studies suggesting this to be even higher^(1-3). When injury strikes, even the best training plan and personal goals can go out of the window, which means that understanding the risk factor for RRIs and trying to reduce the likelihood of injury is very important, especially when training for a demanding event such as a marathon.

Risk factors for RRIs

Since RRIs are so prevalent in runners, it is important to be aware which factors may influence risk. There are a number of proposed causal factor for RRIs in runners, including a sudden increase in training volume or intensity, a change of running surface, incorrect shoe selection and biomechanical imbalances in runners themselves. Common to many of these factors is an increase in high-impact loading, and research suggests that high-impact loading is indeed a key factor in RRI risk^(4,5). Being a novice runner with less than a year’s experience, being a much older runner and not following a structured program also increase injury risk⁽⁶⁾. Also, as discussed in a very recent article by Andrew Sheaff, having a higher bodyweight or a history of previous injury also raises your risk of sustaining an RRI in the future.

Can you test for YOUR risk?

The factors above provide a broad brush overview of whether you fall into the generally categories of runners who are at increased risk of an RRI. But while helpful, it doesn’t provide information on YOU. What might be particularly helpful is some kind of screening procedure to see if you have certain biomechanical traits or muscle function deficits/weaknesses that are specifically associated with an increased risk of a running-related injury. The good news is that some brand new research by a team of US researchers points a way forward, providing runners with a basic self screening test to provide a more accurate picture of their injury risk⁽⁷⁾.

New research

In this study, which was published in the ‘Clinical Journal of Sports Medicine’ researchers from the Department of Orthopaedics, University of Utah set out to identify strength and flexibility measures that are associated with the risk of running-related overuse injuries in recreational runners. To do this, 867 runners registered for the 2019 New York City Marathon were recruited into the study. In the first stage of the study, all the runners were asked to complete a baseline strength and flexibility self-assessment 16 weeks before the marathon date. Following this baseline assessment, the participants were asked to respond to surveys on any running-related injuries they had suffered occurring within four different 4-week ‘training quarters’, which took place at 16, 8, 4, and 1 week(s) before the actual marathon race (November 3^rd 2019).Following the race, the researchers pooled all the data and looked for correlations between key measures of baseline strength and the rate of subsequent injuries while training for the marathon.

What did they find?

When the data was analyzed, it showed that 36.1% of the runners had sustained a running-related overuse injury while preparing for the marathon during the observation period – a high proportion given this period was just 16 weeks long! When the researchers looked for correlations between strength and flexibility scores and subsequent injury risk, there seemed to be no link with flexibility and injury risk. Many of the strength scores also seemed to be unrelated to injury risk. However, one strength exercise showed a remarkably high correlation – the single-leg glute bridge (see figure 1).

Figure 1: The single-leg glute bridge exercise