Researchers looked at data from 417,000 children in 20 countries. They found that children's strength and flexibility are lower now. Children became less flexible after 2000. Body fat is also increasing.

Good physical health in childhood helps prevent diseases like heart problems. But most European teenagers don't exercise enough. Experts say groups must encourage young people to move more.

Some hard words are: decade (10 years), flexible (can bend easily), encourage (give support to do something).

You can watch the original video in Level 3.