A Look Inside SMUs Locomotor Performance Lab

By studying the athletes' biomechanics at the whole-body level, researchers are able to identify areas for improvement. Coaches use the information provided to adjust the athlete's mechanics to enhance force application and performance. When competing at the highest levels, even slight modifications can significantly affect performance outcomes.

Having executed performance-based research since its founding in 2008, the LPL has built an extensive network of potential test subjects and colleagues. The lab has collaborated with military performance experts, strength and conditioning specialists from numerous sports, and track and field organizations from across the globe to investigate the mechanical determinants of speed and power.

Past and ongoing efforts have examined how prosthetic limbs affect gait mechanics and symmetry. The lab uses a variety of approaches to advance physiological monitoring and performance capabilities on behalf of its primary sponsor, the US Army's Medical and Materiel Command. One of the LPL's most recent initiatives includes joining the ambitiousSUB2 project, a new international scientific consortium dedicated to the achievement of a sub two-hour marathon.

To obtain the precise measurements needed for its research, LPL leverages motion-capture technology, high-speed cameras and force plates, among other tools. The lab's motion-capture system comprises 12OptiTrack Prime 17W cameras and is currently being deployed in three different configurations to capture data: on a high-speed, AMTI force-sensing treadmill; on a sprint runway laid over force plates; and in an open lab area, where sports-related collisions are studied.

Prior to acquiring the OptiTrack motion-capture system, LPL developed a high-speed video-based system designed specifically for human performance research conducted by LPL Director Dr. Peter Weyand. The system consists of video cameras capturing at 1K fps (frames per second) and custom MatLab software, and continues to play an important role in LPL's research. Motion-capture capabilities were added in 2013 to achieve higher throughput for analysis so that researchers could accommodate more subjects faster. Considering LPL's video-based system is accurate to 0.7mm, ensuring that level of accuracy or better was a key factor in evaluating solutions.

Many commercial systems are not fully traceable, but with OptiTrack, we can calibrate against known standards so we know our exact spatial resolution. We're tracking events that occur on an extremely short time scale, so it's really important that we're able to validate positional data, explained Dr. Weyand.

Added LPL Research Engineer and Physicist Dr. Larry Ryan, We needed a large field-of-view due to our lab dimensions and a high frame rate, preferably 250+ FPS. The Prime 17W suits our needs perfectly and the open architecture of the OptiTrack system is really attractive; in terms of affordability, there is no comparison.

Researchers interface the OptiTrack system and other technologies using an eSync module, a setup that allows for simultaneous acquisition and synchronization of data streams. For example, on the treadmill, researchers gather motion capture and force plate data from subjects. On the sprint runway, in-ground force plates are interfaced to a National Instruments data acquisition system running LabVIEW system design software. Additionally, video cameras record live video.

For the sports collision application, LPL's force sensors are embedded in a collision push bar that allows researchers to apply measured forces to subjects outfitted with accelerometers. In addition to using standard marker sets within OptiTrack's Motive software, LPL employs a custom marker set and streams the .CSV output available from Motive into its own data analysis package.

Beyond allowing researchers to minimize occlusions, the Prime 17W's ultra-wide FOV can turn most or all of the lab into tracking area, a feature well appreciated by coaches, and 3D motion capture enables subjects to be viewed from any angle for extremely close analysis. The data can then be compared to what LPL's ongoing research has determined as ideal running form, information that will certainly prove advantageous in the sub two-hour marathon quest.

LINK:	http://www.cgw.com/Press-Center/Web-Exclusives/2016/A-Look-Inside-SMUs...
	See more stories from cwg

Most recent headlines