Dead bug

This is an excellent exercise to target the local core muscles, but it may take some practice to coordinate all movements. As with other core exercises, maintain a neutral spine and core activation throughout the duration of the exercise. [ID: dead_bug]

Instructions

First time: Try 1 set, 10 reps

Steps:

Start position: Lay on your back. Raise arms to perpendicular. Raise your legs bending knees to a 90 degree angle. Engage your core throughout this exercise.
Reach your left arm backward, over your head as you simultaneously extend your right (opposite) knee, reaching your right heel toward the floor. Stop the movement just before your arm and leg touch the ground.
Return to the start position
Alternate and perform the dead bug movement with your right arm and left leg

Details

Go slow and breath. If your timing is off, then practice by doing your dead bug in steps: raise your arm and then lower your leg.

Progressions: Add sets, reps. Add weight by holding a dumbbell in each hand.

Little help

Video: Dead bug demo, "Core Exercise: Dead Bug", www.youtube.com/watch?v=g_BYB0R-4Ws

Article: "How to Do the Dead Bug Exercise" from VeryWellFit, www.verywellfit.com/how-to-do-the-dead-bug-exercise-4685852

Video: Up your dead bug game with this cool workout, "5-Minute Dead Bug Workout (No Repeats)", www.youtube.com/watch?v=vnozpFoI8ug

Article: look here for 3 cool Dead bug variations, "I did deadbugs for four months and this core exercise changed my body for the better" by T3, www.yahoo.com/lifestyle/did-deadbugs-four-months-core-070016823.html

Image source: NASM, nasm.org