"Jumping jacks" is an exercise where you jump up and spread your legs wide while clapping your hands overhead, and then jump back to the starting position with your legs together and hands down by your sides. Full definition
If a regular jumping jack is too difficult, step side to side while raising your arms instead. (dailyburn.com)
Select between the higher - impact, traditional jumping jack, or the lower - impact step - out version. (girlsgonesporty.com)
They are effective as a cardio exercise or for warming up just before you get to do other exercises, so reach back to your childhood and start jumping jack. (autogen.co.za)