To be honest, the Functional Movement Screen is not something that I have really paid a lot of attention to. It is becoming a popular topic and attracting increasing attention. I have scanned some abstracts on it periodically, but it never really grabbed my attention. There have been a couple of studies of it in runners (here and here), but they were just descriptive studies and not of much use. The Functional Movement Screen is a screening tool that gives a score based on seven tests: the Deep Squat, Hurdle Step, In-Line Lunge, Shoulder Mobility, Trunk Stability Push-Up, Active Straight Leg Raise, and Rotary Stability. Rather than go into detail here, I refer you to these two blog posts by Chris Beardsley and Paul Ingraham for more good information. Even though the two studies just linked provided normative data in groups of runners, I did not think that it would have a great deal to do with overuse injuries in runners which is probably why I did not pay a lot of attention to it.
Having said that, I just recently did pay some attention to it due to the appearance of this masters thesis from the California State University:
Predicting injuries in NCAA runners using the Functional Movement Screen (FMS(TM))
Padilla, Ricardo, M.S.,
CALIFORNIA STATE UNIVERSITY, FULLERTON, 2014
The Functional Movement Screen (FMS) has shown some efficacy in predicting injury in several different populations. However, no research has examined whether the FMS can predict injury in repetitive motion athletes, such as runners. This study will examine whether the FMS can prospectively predict injury in a group of collegiate (Division I) sprinters and cross-country runners. 64 division I collegiate runners (31 sprinters, 33 cross country) volunteered for this study (35 male, 29 female, age = 19.26±1.16, height = 1.74±0.09m, weight = 63.4±8.9kg). FMS testing was performed and injuries were then tracked throughout the athletic season. Athletes who sustained injuries (FMS Score: 15.9±1.9) had a significantly higher (p < 0.05) FMS scores than those who were non-injured (FMS Score: 14.6±1.9). Logistic regression revealed that the FMS was a good predictor of injury and a one unit increase in FMS score resulted in an increased risk of injury by 1.5 times (P = 0.0 139; 95% confidence interval = 1.1-2.0). The ROC curve resulted in a poor score (<0.70) and was not able to identify cut points for injury prediction. Unexpectedly, higher FMS scores led to an increased injury risk in collegiate runners. It has been suggested that in order to maintain optimal musculoskeletal health, one must have variety in their movements and postures. Since runners do not get variety in movements from their sport/training, perhaps those with lower FMS scores are achieving that variability, and avoiding injury, through their more variable movement patterns.
I don’t have access to the full thesis to evaluate the methods, but nothing jumps out at me as a problem in the abstract. The participants were division 1 collegiate sprinters and cross country athletes, so they are almost elite level runners which means that it may not necessarily be possible to extrapolate the results to non-elite runners.
In the Functional Movement Screen, the higher scores are considered better as the athlete is ‘stronger’, but in this study they showed that you were more likely to get an injury if the score was higher. That is certianly counter-intuitive. As to why, I have no explanation. In the abstract the author offered this:
Since runners do not get variety in movements from their sport/training, perhaps those with lower FMS scores are achieving that variability, and avoiding injury, through their more variable movement patterns
Without seeing any data (which may be further justified in the full thesis), I am not sure I want to go along with that. I am open to anyone who might want to try and offer up a potential explanation.
When I look at the components of the Functional Movement Screen, many are related to “core stability” (even though there is a poor correlation between the Functional Movement Screen and core stability; probably as the Functional Movement Screen measures more than just the “core”). This does raise some thoughts for me: How often do you hear how important core stability is supposed to be for runners; things like “the core is the engine room for running”. I have no doubt that a stronger core is probably better than a weaker core (just like having a strong muscle is better than a weak muscle), but to simply state that it is better and that its the “engine room” is using the wishful thinking fallacy – that is, just making a statement and wishing it was true. It may or may not be true, but you can not make statements and wish or hope it was true. This does not constitute evidence that something is true. I would speculate that the above study suggests (weakly) that the “core strength” is not that important in preventing running injuries.
As always: I go where the evidence takes me until convinced otherwise, and just because you do not like the results of study does not mean you should ignore it.