A muscle can pull through a tendon attached to bone. It does not become a pushing rod. One muscle action can bend a joint, while an opposing action straightens it. Watch the highlighted pull and the attached forearm together. Compare bending with straightening. Follow the highlighted muscle and its tendon across the joint.
The human body · Discover & try
How can a pair of muscles move a joint both ways?
Reading level 2 of 5 · DevelopingChange
Word help
Tendon
Tissue transmitting a muscle’s pull to bone.
Antagonistic pair
Muscles or groups that can produce opposing actions.
Watch · Try · Explain
See how it works
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A conceptual opposing pair. Shapes and angles are illustrative; real movement includes stabilisation and coordinated muscle activity.
What to look for
- One muscle pulls through a tendon and the forearm rotates.
- The opposing pull turns the forearm the other way.
Explain what you noticed
A different virtual joint needs to reverse its movement. Which strategy fits the muscle principle?
Keep this idea: Opposing muscle pulls can move a joint in opposite directions.
Follow the sources
- NIH NIAMS — Health Lesson: Learning About Muscles
- NIH National Cancer Institute — Structure of Skeletal Muscle
Source material checked 2026-10-29. Explanations and activities by Nepedia. Source links do not imply endorsement.
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