Biomechanics principally stems from two disciplines, mechanics and biology.
However, both the application and language of the mechanical constructs
are not always adhered to when applied to biological systems, which can
lead to errors and misunderstandings within the scientific literature. Here
we address three topics that seem to be common points of confusion and
misconception, with a specific focus on sports biomechanics applications: 1)
joint reaction forces as they pertain to loads actually experienced by biologi-
cal joints; 2) the partitioning of scalar quantities into directional components;
and 3) weight and gravity alteration. For each topic, we discuss how mechan-
ical concepts have been commonly misapplied in peer-reviewed publications,
the consequences of those misapplications, and how biomechanics, exercise
science, and other related disciplines can collectively benefit by more carefully
adhering to and applying concepts of classical mechanics.