I
f you play “Casey Powell Lacrosse 16,” then you’ve seen kinematics at work.
Video games use the same technology as scientists around the world who are studying how the human body moves in space.
Sensors are placed on key body parts to capture motion and then depict an image of how those points interact with each other. A high speed shot by Casey Powell in real life transforms into a digital representation.
But more importantly, the sensors provide a growing body of research related to lacrosse performance and safety, the results of which will inform the development of sport-specific injury prevention programs.
Since its inception in 1998, US Lacrosse has invested more than $1 million in research that has provided empirical support for initiatives in player safety and competition integrity.
The traditional focus of these studies has been injury surveillance.
However, the field has shifted to an evidence-based, multi-disciplinary approach. The US Lacrosse Center for Sport Science, launched last May, recently funded research on youth athletes’ movements that relates findings to injuries.
Synchronizing sensors with video, a current study at George Mason University measures head impacts in high school boys’ and girls’ lacrosse. Due to their sensitivity in detecting motion, pairing action on the field with impacts shown on film provides a better overall picture.
“The field historically has waited for injuries to occur and then tried to determine through self-report of the athlete and looking at injury records retrospectively what has happened,” said Dr. Shane Caswell, the executive director of George Mason’s Sports Medicine Assessment Research and Testing (SMART) Lab, who grew up playing lacrosse with Powell in Watertown, N.Y. “By combining video analysis with these types of tools, it gives us a sharper image of what the true state of affairs is in the sport and how injuries are really occurring.”
Another recent focus for Caswell’s research team is a BioHarness, a lightweight strap that wraps around a player’s chest and helps determine the physiological demands of sport participation by player position, including work-rest ratios, while monitoring key vitals such as heart and breathing rates. The monitor also can detect changes in an athlete’s work rate when it’s a close game versus a blowout.
Taking kinematics one step further, George Mason is studying biological factors by looking for salivary biomarkers of brain trauma. Dr. Nelson Cortez of the SMART Lab leads one of just two research groups in the world using diagnostic ultrasound machines to develop novel algorithms to examine muscle kinematics.
“Not only looking at what people are doing when people play the sport, we’re looking inside their bodies while they play the sport, and he’s developed methods to image what’s actually happening inside the musculature,” Caswell said.
Heather K. Vincent, the director of the University of Florida Sports Performance Center, approaches kinematics similarly, using a US Lacrosse grant to assess the risk of lower body injuries by taking her cameras to the field to capture movements of youth players with and without lacrosse sticks — particularly studying their form while running, jumping and squatting as it relates to knee strength around the ACL. Not singling out the knee joint itself is indicative of a “train of thought [that] is really catching fire right now,” Vincent said.
“The body is really closely linked together,” she added. “Probably over the last five years or so, that message has become quite clear, that we don’t just focus on one body part. We have to look at the whole kinematic chain, the whole connection of all the joints and body parts together, or we’re not really seeing the whole picture.”
Scientists now study motion not only by looking at environmental factors of what the body is encountering in space, but also by examining all three planes of motion — sagittal (left to right), frontal (front to back) and transverse (top to bottom) — deviating from the original concept that motion, such as running, goes in only one direction.
With US Lacrosse grants, Caswell and Vincent are observing youth players more closely to help correct movement patterns early. Vincent stresses playing multiple sports, going hand-in-hand with examining kinematics as a whole instead of zooming in on one joint or muscle.
“What’s really cool about US Lacrosse is they’ve taken an interest in doing research on their youth athletes,” Caswell said. “They’re really starting with the kids and developing them as they grow as athletes, which is different from a lot of the research in sports settings.”
Other sport scientists have caught wind of US Lacrosse’s commitment to research. Researchers at the University of Alberta plan to apply for a grant to help fund a mouth-guard performance study.
“We’re literally the center of a wagon wheel,” said Dr. Bruce Griffin, director of the US Lacrosse Center for Sport Science. “There’s a lot of spokes that represent different research locations around the country, but there’s a common goal for many of them that center around the lacrosse athlete. They’re working to make that experience better. As you get people to have that conversation through the center of the wheel with all the spokes going in different directions, there’s a synergy.”
According to Vincent, start small, think big, and this new wave of thinking will help parents, coaches and teams yield smart decisions, making the safety and proper development of the lacrosse player a priority.
What We Know
Five findings of kinematic studies:
1. In girls’ lacrosse especially, many stick and body impacts occur without a penalty.
2. Previously, most impacts in boys’ lacrosse were due to helmet-to-helmet contact, as gleaned by filming nearly 1,000 games. US Lacrosse, NFHS and NCAA rule changes introducing stiffer penalties for such collisions have reduced concussions.
3. High school players with mild pain in the lower back move more slowly, bend their knees more when throwing the ball and cannot fully rotate their spine. “Not a lot of them were emphasizing core strengthening and working on strengthening of the hips and gluteus muscles,” Vincent said. “Even though the pain was in the back, the back was the victim.”
4. When compared with a throw, an overhead lacrosse shot relies more on trunk extension and rotation as a youth male player follows through, and less on shoulder rotation.
5. Long-pole defenders rely more on trunk lean to develop fast ball speeds than midfielders and attackmen, who use other strategies like upper-body rotation and increased wrist motion.