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)-.
Monitor Your Jumps. Ensure that your jumping jacks remain aerobic by monitoring your heart rate response to the exercise. An exercise that elevates the heart rate between 60 and 90 percent of your maximum heart rate is considered aerobic.