Shorten, lengthen, hold
A muscle can work while shortening, lengthening or holding its length approximately steady.
Distinguish the three contraction terms using one named muscle and one known load.
The manual names concentric, eccentric and isometric contraction. The app adds a clearly labeled explanatory model: elbow flexors raise a light represented load, control its lowering, or hold it.
The model specifies the muscle and movement phase. It does not label an entire yoga pose as having one contraction type.
One muscle, three kinds of work
The same load can meet shortening, lengthening, or holding.
This is a simplified learning diagram. It is not a reviewed anatomical illustration.
Low Plank / Chaturanga
Watch the same elbow-flexor model in each phase. The load stays the same; the direction and muscle behavior change. No real weight or movement is required.
Hold one arm out in front of you and keep it there for a slow count of ten.
Notice: The muscle is working hard and not changing length. That is the third kind of contraction.
This is noticing, not instruction. Move as little as you like, stop at any point, and watching instead of moving is a complete way to take part.
The modeled elbow flexors lengthen while controlling a descending load. Which contraction term applies?
Pause before opening Practice. Say the distinction in your own words.
Which muscle is the question about? Is the example moving or holding?
The elbow demonstration is an authored supplement checked against an external anatomy source. A still picture cannot establish all the muscles' contraction behavior.