Biomechanics

Biomechanics is a specialized branch of biophysics. It focuses on the mechanical aspects of biological systems. This study covers many different scales of life. It includes whole organisms like humans or animals. It also examines organs, cells, and tiny cell organelles. Scientists even study the mechanics of individual proteins.

By using the methods of mechanics, researchers can understand how living things function. They look at how structure and motion work together to support life.

One major area of study is biofluid mechanics. This field examines how gases and liquids flow around or inside organisms. For example, scientists study blood flow in the human cardiovascular system. In many cases, whole blood is treated as an incompressible Newtonian fluid. However, this model changes at microscopic scales. When blood moves through very small vessels called arterioles, individual red blood cells matter.

In small vessels, the Fahraeus–Lindquist effect can cause a decrease in wall shear stress. If the vessel becomes even smaller, red blood cells must squeeze through in a single file. This leads to the inverse Fahraeus–Lindquist effect, which increases wall shear stress.

Another important subfield is biotribology. This is the study of friction, wear, and lubrication in biological systems. It is often used to study human joints like the hips and knees. Researchers use contact mechanics to see how surfaces rub against each other. This is important when evaluating things like tissue-engineered cartilage. Scientists also look at subsurface damage caused by motion. Understanding these mechanical interactions helps explain how joints stay healthy and move smoothly.

Scientists also use computational biomechanics to study life. This involves using engineering tools like the finite element method. These computer models allow researchers to predict how biological systems respond to different forces. This is very helpful in medicine. Doctors use these simulations for surgical planning and training. It allows them to see how an anatomy will respond without needing to perform a live surgery.

This method is now used widely across many different fields of biomechanics.

The history of this science stretches back to ancient times. Aristotle is often considered the first biomechanic. He wrote about animal anatomy and the motion of animals. He described how the ureter uses peristalsis to move urine. Later, Galen wrote a medical book that became a standard for 1,400 years. During the Renaissance in the 1490s, Leonardo da Vinci studied anatomy through a mechanical lens. He analyzed how muscle forces act along lines between their origins and insertions. He also studied how joints function and even mimicked animal features in his machines.

Comparative biomechanics applies these principles to non-human organisms. This can be used to understand humans better or to learn about animal adaptations. Researchers often study animal locomotion, such as running, jumping, or flying.

Locomotion requires energy to fight against gravity, drag, inertia, and friction. This field overlaps with many other sciences like ecology and paleontology. It also helps in biomimetics. This is when engineers look to nature to find solutions for human problems.

Biomechanics also plays a huge role in sports. Sports biomechanics applies mechanical physics to human movement. It looks at how the body uses muscles, joints, and bones during a task. This helps athletes improve their performance and avoid injuries. Experts study the movement of the body and sports implements, like a javelin or a hockey stick. By understanding these mechanics, people can master new skills and recover from injuries more effectively. This field connects biology, physics, and engineering to explain the moving world.