Researchers in France are looking at the repetitive shocks experienced by runners and how they adapt their running patterns according to different running conditions.
In the European Union and the United States, more than 110 million people run recreationally but the sport has a high injury rate. One peer-reviewed medical study found that nearly half of all recreational runners who train regularly will suffer from running-related injuries in a given year.
According to the Acoustical Society of America, one of the reasons for these injuries is that runners endure many shocks from the impact of running, and these cause vibrations that travel from the foot throughout the entire body.
Preliminary findings of the new research were presented at Acoustics ’17 Boston, the third joint meeting of the Acoustical Society of America and the European Acoustics Association.
“The way runners manage the three-dimensional components of the vibrations, especially in terms of frequency, is not well understood. It’s very difficult to measure the vibrations accurately,” explained Delphine Chadefaux, a post-doctoral researcher who focuses on acoustics and biomechanics. “The study looked at which biomechanical parameters runners adapt to tune the shock-induced vibrations according to different running conditions.”
The research team at Aix-Marseille Université measured the kinematics of the runners with a motion capture system. The vibrations were measured with small accelerometers placed on the skin at various points of interest, such as at the foot, knee, shank and hip.
“We wanted to understand how the vibrations were propagating and how the human body was adapting to them,” Chadefaux said.
Preliminary results of the study show that at various speeds the human body is changing to adapt to these vibrations and stabilise the energy as it flows to the upper part of the body. The same processes are at work to protect the upper body whether you run slowly or quickly.
Chadefaux believes the study can help fill a gap in the existing research literature.
“Many of the studies involved in running or shoe development do not focus enough on shock propagation,” she said. “We would eventually like to use the insights that we garner to advance the collective understanding of how to prevent running injuries and design better running shoes.”
Chadefaux and her colleagues are also studying tennis, investigating how vibration induced by the tennis ball’s contact with the racket propagates through the human body.