Muscle action analysis
Tue, Feb 23, 2027 · Week 6 · Human Anatomy & Physiology (Human Body Systems)
Today's goal: Analyze agonist and antagonist muscle pairs and revise your model labels.
What a finished product looks like
This is a model of the work you should turn in today. Use it to check your own: match the structure and the level of detail, do not copy it. Your data and wording should be your own.
Chosen movement: bending the elbow (elbow flexion).
- Agonist (prime mover): biceps brachii. It contracts to flex the elbow.
- Antagonist: triceps brachii. It relaxes and lengthens to allow flexion; it would resist or reverse the movement.
- Synergist: brachialis. It assists the biceps and helps stabilize the elbow during flexion.
Reversed movement (elbow extension): the roles flip. The triceps becomes the agonist and the biceps becomes the antagonist.
Revised label card: I marked the biceps on my Maniken as AGONIST for flexion and the triceps as ANTAGONIST, and added a note that the labels swap for extension.
Why it matters: When the agonist and antagonist of a pair are unbalanced, the joint is more prone to overuse injury, which is why physical therapists train both sides of a pair.
Also due today: Submit your analysis and revised label card as a single document or photo.
WebXam problem for today's skill
One exam-style question that uses exactly what you practiced today. Try it before you reveal the answer, then read why each choice is right or wrong.
Tap an answer to see the full explanation. Nothing is recorded or graded.