Anyone who’s ever driven a truck, a bus or a bulldozer for a long period of time might have considered what kind of long-term damage the constant rumbling and bumping of those massive machines under them might be doing to their bodies.
A pair of researchers in Kinesiology is using movie and video-game grade technology paired with robotics to get the answer. Master’s student Danielle MacIntyre and Joel Cort, her professor and academic supervisor, are studying the effects of constant vibration and sudden movements on people’s muscles.
“Our muscles were never designed to go through these constant vibrations so they become less optimal at responding to sudden movements,” explained Dr. Cort.
Cort’s hypothesis is that muscle spindles — the sensory receptors that detect changes in the length of muscles, as well as the rate of that change, and send that information to the central nervous system — become damaged if they’ve been exposed to chronic vibration for long periods of time. That damage impairs the ability for those muscles to react the way they normally would to protect the body from abrupt disturbances, heightening the likelihood of further, more serious muscle and joint injuries, he believes.
In their second-floor lab in the Human Kinetics Building, they’ll secure research participants to a car seat perched atop a six-legged hexapod robot. Those not in the control group will experience vibrations levels similar to those in an earth-mover or a tractor-trailer. After 10 minutes they will suddenly “perturb” the subjects with a slight jerking movement to the left or right, or front to back.
Electrodes strapped to the participants’ body records the bursts of electrical activity that come from the muscles as they respond to the mechanical disturbances. Using motion capture technology, the researchers strap reflective silver balls to the subject so the video cameras situated around the room can record digital images, providing a complete picture of how the skeleton and muscles are reacting and interacting.
The experiments are all part of a study MacIntyre is conducting that’s funded by the Ontario Workplace Safety and Insurance Board’s Centre for Research Expertise for the Prevention of Musculoskeletal Disorders at the University of Waterloo.
“We want to know why there’s such a higher rate of back injuries for those who drive trucks, buses, large earth movers and that kind of equipment and to see if anything can be done to prevent them,” Cort said.
MacIntyre is hoping to recruit at least 20 healthy male subjects who have never experienced a back injury before to participate in the project. If you’d like to volunteer, contact her at email@example.com.
Watch a video about their research: