There is also a special null type, the type of the expression null, which has no name. Because the null type has no name, it is impossible to declare a variable of the null type or to cast to the null type.
Transcript of Muscles Used for Jumping Jacks! Muscles Used for Jumping Jacks! FONTS. Muscles of the Abdomen- Anterior View. Rectus Abdominus. : Helps stabilize the movement to create pressure through a jumping jack. Muscles of the Lower Extremity. Anterior View (leg)-.
Report Abuse. Jumping jacks helps with the blood circulation in the body and gets the heart rate up. It helps burn calories kind of like jogging or running, but you have to keep doing it for a significant amount of time and not stop right when you get tired in order to burn calories.