George Berkeley
Berkeley argued that forces and gravity, as defined by Newton, constituted "occult qualities" that "expressed nothing distinctly". He held that those who posited "something unknown in a body of which they have no idea and which they call the principle of motion, are in fact simply stating that the principle of motion is unknown." Therefore, those who "affirm that active force, action, and the principle of motion are really in bodies are adopting an opinion not based on experience." Forces and gravity existed nowhere in the phenomenal world. On the other hand, if they resided in the category of "soul" or "incorporeal thing", they "do not properly belong to physics" as a matter. Berkeley thus concluded that forces lay beyond any kind of empirical observation and could not be a part of proper science. He proposed his theory of signs as a means to explain motion and matter without reference to the "occult qualities" of force and gravity.
Biomechanics
The next major bio-mechanic, Giovanni Alfonso Borelli, was the first to understand that “the levers of the musculature system magnify motion rather than force, so that muscles must produce much larger forces than those resisting the motion”. Using the works of Galileo and building off from them, Borelli figured out the forces required for equilibrium in various joints of the human body. He even discovered the human center of gravity and air volume as well as  muscle elasticity. His work is often considered the most important in the history of bio-mechanics because he made so many new discoveries that opened the way for the future generations to continue his work and studies.