The functional movement screen (FMS) has been a hotly debated topic recently for athletic performance. Does it predict injuries? Does performance on the FMS have any predictive values for athletic performance? In the latest issue of the International Journal of Sport Physiology and Performance, Chapman et al investigate whether there was a relationship between performance on the FMS and track and field performance in elite U.S. track and field athletes. 121 athletes that were part of the U.S. high performance program were screened at the end of the 2010 competitive season and their performances in 2010 and 2011 were tracked. The FMS consisted of a deep squat, hurdle step, in-line lunge, trunk stability push up, active straight leg raise, shoulder mobility, and rotary stability tests.
Results:
• In broad terms, those individuals with a higher FMS score improved their season’s best performance more from 2010 to 2011. For example, when looking at all tier 1 and tier 2 athletes, those with the higher FMS score improved their performance by .21%, whereas those with the lower FMS score saw their performance decline by .97%.
• There are differences by event group. Sprints/hurdles and jumps saw a decrease in performance regardless of FMS score, but the higher scoring athletes only experienced a .06-.08% reduction in performance compared to .29-.35% reduction for the lower scoring athletes.
• The distance athletes saw an almost .05% increase in performance with the higher scoring group, compared to a more than .5% reduction in performance for the lower scoring group.
• With the exception of the sprinters/hurdlers, those athletes without an asymmetry between the two sides of the body increased their performance, whereas those with an asymmetry saw a reduction in performance. The sprinters/hurdlers saw the opposite happen.
Looks good for the FMS right? A few thoughts on this. First, none of the increases or decreases in performance were statistically significant. For example, a .04% improvement in distance performance would have hypothetically improved Galen Rupp’s 28:47 performance in the 2013 outdoor nationals by .011 seconds. Second, there was no statistically significant correlation between the FMS score and performance changes.
Now, by definition elite athletes are not going to improve their performance much from year to year. Also, at that level very small differences in performance can make the difference between medaling and not placing, so statistical significance needs to be considered with this in mind – a small change in performance may make a big difference to an elite athlete but may not register statistical significance.
A thought regarding asymmetries. Track and field events, especially the jumps and throws, develop and require asymmetries. All jumps and most throws involve levering off one side of the body. This means there will be an asymmetry between the two sides. This is true for a lot of sporting events. While the FMS confirms this asymmetry, it doesn’t mean that this is an injury concern – it’s an adaptation from participating in the sport.
Chapman, R.F., Laymon, A.S., and Arnold, T. (2014). Functional movement scores and longitudinal performance outcomes in elite track and field athletes. International Journal of Sports Physiology and Performance, 9, 203-211.
