If the instructions are confusing, you're not alone.
"The terms are important if a client wants to know them," said Josh Stolz, a senior trainer at an Equinox fitness center in New York City. But, "understanding how the body moves, which muscles move you in which direction, and the exercises associated with them, is really the key."
Stolz said trainers can get too wrapped up in using anatomical terms to impress clients.
"In America we like to shorten everything: tris and bis instead of triceps and biceps, quads and hams instead of quadriceps and hamstrings," he said.
Often a touch is worth a thousand abbreviated words.
"I'm very tactile when I train. So if a client can't activate a muscle, I'll actually rub it so they feel what I'm talking about," he said. "If I'm trying to get someone's rhomboids (upper back muscles) to fire, I'll just poke underneath the shoulder blades."
The training is easier, he maintains, if the client isn't forced to over think the movement.
"I can think of one trainer who just talked and talked and talked," he said. "Finally I sat him down and said 'You need to use as few words as possible to explain a movement.' Teaching a client a brand new movement is hard enough without having the verbiage going on."'
Stolz thinks most clients can learn a new movement on their own. The right amount of coaching speeds up the process, but too much inhibits it.
Sara Ivanhoe, a yoga instructor with YogaWorks, said often anatomical terms don't translate well even to the most intelligent student.
"If I'm telling someone to soften their floating ribs in, or rotate their inner upper thighs back, people often have no idea what that means," said Ivanhoe, who is based in Los Angeles.
A student of Sanskrit, Ivanhoe uses the ancient language of Hinduism alongside her anatomical vocabulary to connect students to the spiritual side of the practice, and to each other.
"Sanskrit is one of the things that unify us as yogis. It's the international yoga language," she said.
If I go to Italy and they say 'trikonasana' (triangle pose), I don't need to know Italian to know what to do."
She said the sound of Sanskrit itself is meant to be healing.
"Sanskrit is what's called a vibrational language," she said. "Hearing it still has value even if the practitioner never learns the meaning of a word of it. The sound itself is meant to unlock things."
Ivanhoe said the colloquialisms created to enhance communication between student and teacher don't always succeed.
"The point of the teacher is to have all these tools. The job of the teacher is to be watching. If I give a direction to lengthen the spine and nothing happens, I'll try something else," she said.
"The job of the student is to get your questions answered."