- Biomechanics is a tool to understand human movement that can be applied to enhance athletic performance and prevent injury.
- Performance of a skill can be broken down into multiple layers of components, ranging from muscle strength to joint trajectories.
- Tools to measure human movement include video, accelerometry, medical imaging, and 3-D motion capture.
- Optimal movement is affected by body size and shape. Elite athletes move optimally and this knowledge can be used to coach and train others.
Robotics, physics, mathematical analysis, imaging, and computer simulations are the some of the latest tools in the quest to improve athletic performance. Together they are used in the study of biomechanics-the physiological analysis of the interaction of forces and effects of forces on and within the human body. Biomechanics researchers are able to examine each aspect of a movement to enhance performance and to understand the mechanisms of injury.
Measuring Movement
Measuring movement can take place in a lab or on the playing field. Dr. Besier often uses simple video analysis to assess temporal-spatial relationships, steps, stride length, and other components of movement. From there, he uses more complex equipment to study the player’s kinematics (three-dimensional motion), kinetics (the forces of motion), and muscle activation.
One of the challenges of biomechanics is that elite athletes can perform at their highest level but have different techniques. Two tennis players can serve in completely different ways. But is any one way better? Is there an optimal way? Or one with less chance of causing an injury? We have to take into consideration that we all have different constraints, such as body sizes, range of motion, and strength. Applying robotic techniques can help determine whether an athlete is moving optimally by estimating muscle movement to calculate effort.
Preventing Injuries
Most musculoskeletal injuries have a mechanical etiology. The stress applied exceeds the strength of the tissue. The extent of the damage is related to the magnitude, rate, and frequency of loading, and recovery and rehabilitation must incorporate the body’s ability to adapt to these mechanical loads (including the body’s adaptations to over- and under-use). Tibial fatigue fractures, for example, are caused by stresses in the bone, which are influenced by loading factors, such as distance or frequency, along with bone mineral density and bone shape. In addition, the biological response of tissue to different loads can induce tissue to change.
An anterior cruciate ligament (ACL) injury, for example, occurs when the load exceeds the strength of the ligament, taking into consideration factors such as posture, muscle forces, and ligament strength. To prevent such an injury, an athlete needs to reduce external loads (by improving perception skills to anticipate movement), improve muscular support of the external loads (through appropriate training programs), and/or grow stronger ligaments. (Ligaments will adapt to their mechanical environment and potentially get stronger with loading.)
If you understand the mechanisms behind injury, then you can prevent it.
