This quick core routine begins with the plank exercise. The plank provides a great warm-up that engages all the muscles of the core: the rectus abdominis, the internal and external obliques, transversus abdominis, the hip flexors, the erector spinae and multifidus.
Begin in the pictured position. Keep your torso straight and rigid and your body in a straight line from ears to toes with no sagging or bending. Hold the position 15-60 seconds while maintaining control.
To increase the difficulty and intensity of this movement, alternate lifting one arm out in front of you while maintaining your posture for 10 seconds and repeating on the other side. You can do the same with each leg, by lifting your foot up and holding that position for 10 seconds and repeating on the opposite leg.