How much variation is normal in child development when might you or a parent become concerned about development

3 yrs to 5 yrs, that’s when said child’s Cognitive development is growing to a greater extent, also said parent should be careful about what he/she says around said child, hope this helps :D if not Call me a Weeb (optional)

the more fit you are, the faster the recovery. your heart rate drops most sharply in the first minute after you stop exercising; it should then fall about 20 beats a minute—a drop of less than 12 beats a minute is considered abnormal. this “recovery heart rate” is measured as part of an exercise stress test.