On top of having a cool-sounding name, the Superman is an effective core exercise that remains popular in the fitness world.

Here’s how the “Superman challenge” is supposed to go. People line up in two rows facing each other, extend their hands towards each other and hold hands to form a cradle of arms between them.

But the Superman exercise is anything but—providing ... You can also fire up this player by lifting up just one arm and the opposite leg at a time (for example, your right arm and left leg ...