Become a Personal Trainer
Every Muscle Around A Joint Has One Of Five Jobs, And The Level 2 And 3 Course Has You Name Them So Anatomy Stops Feeling Like A Wall Of Latin
From the FASTER syllabus: this article is taught in full in The honest route from scratch to qualified →
In short: Criterion D/617/8589 5.10 asks a learner to describe the role of the muscles around a joint in producing, controlling and ending a movement. The course names five roles. The agonist starts and carries out the movement, the antagonist opposes it and controls speed and range, synergists assist, fixators steady the origin of the agonist, and stabilisers counteract unwanted movement. The worked example is elbow flexion, with the biceps brachii as agonist and the triceps brachii as antagonist.
Anatomy is a list of jobs, and the jobs are easy to learn
Plenty of people weighing up a personal training course expect anatomy to be the hard bit. The industry helps that along by making it sound like a wall of Latin. Criterion 5.10 on the route to Level 3 takes it down to size: describe how the muscles around a joint produce, control and end a movement.
One of the things you learn on our CIMSPA-recognised personal training course is that those muscles work as a team, and each member has a job.
The five jobs
The course says muscles around a joint work in a coordinated way. Here are the roles, with the elbow bending as the example.
Agonist. The primary muscle that starts and carries out the movement. In elbow flexion, the biceps brachii.
Antagonist. The muscle that opposes the agonist and helps control the speed and range of the movement. Here, the triceps brachii.
Synergist. Muscles that assist the agonist, often by stabilising neighbouring joints. The brachialis and brachioradialis help the biceps brachii.
Fixator. Muscles that steady the origin of the agonist so it can exert more force. The rotator cuff muscles do this at the shoulder during arm movements.
Stabilisers. The fifth role, muscles that counteract unwanted movement around the joint.
Why this is lighter than it looks
Nobody needs the whole body memorised before day one. The pattern is the same at every joint: something starts the movement, something controls it, something helps and something steadies. Learn the pattern at the elbow and you can ask the same four questions at the knee, the hip or the shoulder.
How the course teaches it
The FASTER course is visual and interactive. You read the lesson, listen to it, and answer in writing or by dictating your answers. The roles come with pictures and with your own examples, so they stick beyond the exam.
Where to go next
Later in the FASTER journey, PT Manager lets you watch these roles in real clips with its live skeleton tracking. PT Manager is free with any FASTER course and opens when you sign up.
The honest route from scratch to qualified is on the become a personal trainer page. The anatomy unit sits in the Level 3 Personal Trainer course.
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You just read one answer. The course is all of them.
The honest route from scratch to qualified — taught by the people who wrote it, with free return access for life. The price is on the page, payment plans at checkout, no sales calls.
Also worth a look: Level 3 Personal Trainer, where the anatomy lives.
See what the course covers →Frequently asked
What does criterion 5.10 ask for?
To describe the role of the muscles around a joint in producing, controlling and ending a movement.
What are the five muscle roles?
Agonist, antagonist, synergist, fixator and stabiliser.
Which muscle is the agonist in elbow flexion?
The biceps brachii. The triceps brachii is the antagonist, and the brachialis and brachioradialis are synergists.
Do I need to memorise Latin names before I start?
No. The course teaches the roles first and the names come with use.
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