Over the years I've earned personal training certifications with ISSA, ACE, and NASM. I learned a lot of good things from each organization, but I really like the emphasis that NASM puts on postural assessments and body movement. One area they focus on is different planes of motion and I'm not talking about Boeing. Below is a summary of the three planes of motion our bodies work within.
Sagittal- The sagittal plane divides the body down the middle into left and right halves. Exercises in this plane include walking, running, pushups, curls, lunges, rowing, squats, etc. (any type of activity that involves flexion and extension)
Frontal- The frontal plane divides the body into front and back. This involves abduction and adduction exercises. (sideways movements) Exercises that take place in this plane include lateral raises, shrugs, and jumping jacks.
Transverse- The transverse plane divides the body at the waist into upper and lower body sections. This deals with rotation types of movements. Common exercises include cable wood chopping, Russian twists, and swings for tennis and golf.
Some exercises will involve different planes of motion depending on how strict one's form is and if one is doing pullups or chin up variations instead.
The reason I like the emphasis on different planes of motion is because we do not move like robots. Think of a football running back starting and stopping and spinning as he jukes a defender or how dancers move. They are smooth and flowing and don't just move in one plane. Our bodies make fluid, twisting, compound movements, yet many people's exercise routines and most machines at the gym involve isolated movements that are dominant in the sagittal plane. I'm not bashing isolation exercises, I just think it is beneficial to incorporate some functional fitness into your workout too.