I am pretty sure it is an ab workout that is safe for pregnant women. We have not covered pregnancy thoroughly in my medical science so far, I'm so sorry.
The YMCA and similar programs give kids an opportunity to take part in appropriate activities and show them what they can do themselves. They have something to go off of, and take that with them for the rest of their life.
Answer:
An isometric exercise is an exercise in which a muscle is tightened for about 5–8 seconds and there is no body movement.
True is the answer to your question I believe