HOW: While lying supine, relax your arms at your side with your palms down. Bring your knees up and place your feet flat on the ground. Place the slider underneath one foot (make sure to use a smooth floor surface!). As you push down into the slider lifting your hips up, bring your other knee towards your chest. While keeping your hips up, straighten the leg out using the slider. The farther you go out the more difficult it will be. Then, while keeping your hips raised, slide your foot back into your hips.
FEEL: You should feel your hamstring, glutes, and core muscles working.
COMPENSATION: Don’t push down into the ground with your arms too much, only use that to help stabilize your body. Keep your torso straight as you bridge up, don’t twist. Control the slide out and back in, don’t go too fast.