Breaking Speed Barriers: How Biomechanics Shapes Athlete Performance
One of the key differences between fulltime professional sport and business I’ve found over the last five years is the ability to research. By that I mean the availability of time to “deep dive” into an area and assimilate multiple perspectives to arrive at a sound perspective.
As time is short for many working in the front lines of sport, so in this section I will review research papers, some old and some new, and share my thoughts on them and how I see their application in the real world.
In the Exploring Biomechanics and Performance blog, I mentioned the following paper:
Muscular strategy shift in human running: dependence of running speed on hip and ankle muscle performance
This paper is often overlooked by performance and rehab specialists. In my opinion it is one of the incredibly insightful papers that helps synthesize a lot of what we see in the real world, and even more so what we see in SpeedSig. Given the background most sport science graduates have in physiology, it is easier to describe this work in terms of an LT1 break point in gas exchange physiology. Muscle recruitment patterns change as an athlete attempts to express greater speed, and there is a point, ~7m/s according to the authors, that there is a marked change, effectively a breakpoint . Those changes in muscle recruitment then also contribute to the athlete changing from a step length focused model to a step frequency one.
Elite sprinting: are athletes individually step-frequency or step-length reliant?
Taking this a step further, the work of Salo et al. (below) illustrates that individuals vary in their modulation between step length and step frequency i.e. some tend toward length dominance as a means to increase speed while some tend toward frequency. NB: This is not an absolute. Both variables must increase but the observation is that different individuals may have slightly different strategies.
As a practitioner, we then need to consider Dorn et al.’s paper in that light i.e. different athletes may have slightly different recruitment patterns and therefore speeds at which they may or may not be efficient / effective. This bears consideration when as coaches we develop training interventions. We should consider the individual biomechanical “signature” of the athlete, their capacity to generate speed efficiently and how that may impact load on specific muscle groups.
