Bird Dog

How to do it

Start on hands and knees, wrists under shoulders, knees under hips, spine long. On the exhale, reach the right arm forward and the left leg back until both are level with the spine — without letting the hips tip or the lower back sag. On the inhale, draw the elbow and knee back toward the floor (or lightly together under the body). Switch to the left arm and right leg on the next exhale. Keep alternating, slow and controlled, the torso dead still while the limbs move. One rep is one side.

Why it's good for runners

Running is a long series of single-leg balances, and the trunk has to resist twisting with every stride. Bird Dog trains exactly that — the deep anti-rotation core that keeps the pelvis level and the form efficient when the legs tire. Unlike a static plank, it challenges stability while a limb moves, which is closer to what running asks. As one alternating movement on a single card, it's easy to learn and easy to film as a loop.

Common mistakes

Don't let the hips rock side to side as you switch — the point is the torso staying square and still; go slower if it wobbles. Don't overarch the lower back to lift the leg higher; reach the foot back and long instead of up. And keep the neck in line with the spine, gaze down.