- This is a reciprocal movement, so the left arm and right leg move at once, and vice versa.
- While kneeling on all-fours, exhale fully and feel your oblique abs lock your ribs down.
- Keep your abs tightly braced to hold this ribs-down position and tuck your tailbone under.
- While holding this position, reach your arm straight forward and your opposite leg straight behind you.
- Keep your abs tight and do not let your ribs flare or arch your lower back as you lock out your shoulder blade and opposite-side glute.