Center of mass (CoM)
- an object's mean position of mass; that is, a point that is perfectly surrounded by an equal amount mass in all directions.
Center of gravity (CoG)
- point where gravity
appears to act. Since the human body is so small compared to the earth, we can assume gravity acts uniformly on the body, and that CoG and CoM are the same.
- Example, the CoM of the human body while lying down or standing straight up is close to our navel. However, it is possible that during a resistance exercise, the combination of the body's weight and the weight of the resistance will place the combined CoM outside the body. For example, during the mid-portion of a back squat the CoM would be several anterior to the naval.