Straight Leg Fire Hydrants
To do the Straight-Leg Fire Hydrant, start quadruped on the ground with your hands under your shoulders, your knees under your hips and your feet flexed. Unlike with the Bent-Knee Hydrant, with the Straight-Leg Variation, you will straighten your leg out to the side in line with your hip before lifting.
Keeping your arms straight, lift your straight left leg up toward the ceiling. Do not bend the knee. Squeeze your glute as you lift and make sure to keep your arms straight. Do not bend your arms and lean away just to get your leg higher up.
Hold for a second or two at the top then lower back down. Tap your foot down and repeat. Make sure that you lift straight out to the side and keep your leg straight. You want to make sure you are lifting basically straight up to the side. Complete all reps on one side before switching.