Which data-gathering activity would be useful for a biomechanical analysis? creating a graph that compares the salaries of professional gymnasts comparing the numbers of female gold medalists and male gold medalists in gymnastics tracking the increase in the number of gymnastics programs in a city over the course of a decade measuring the angle at which a gymnast’s body bends during an aerial flip done

Biomechanics is the study of mechanical laws that relate to the movement or structures of an organism. Therefore the answer is, measuring the angle at which a gymnast's body bends during an aerial flip is a biomechanical analysis. 

In analyzing the exact position of the athlete's body structure, one can understand how to properly execute the technique or how the athlete can improve better on his/her technique. Studying the structure leads to comparable data that can be used to determined records on human anatomical structures during specific activities. Learning how body structures moves can also contribute to preventing injuries or further injuries from occurring. 

Wash your hands often and recycle your trash instead of just throwing it away.