The bridge exercise is a great way to isolate and strengthen the gluteus (butt) muscles and hamstrings (back of the upper leg). Performed correctly, it is a good exercise for core stability and a strengthening exercise that targets the abdominal muscles, as well as the muscles of lower back and hip. If you have ever been in rehab, you have probably done this exercise.
1. Lay on your back with your hands by your sides, your knees bent and feet flat on the floor ensuring your feet are under your knees.
2. Next, tighten your abdominal and buttocks muscles. Slowly raise your hips up to create a straight line from your knees to shoulders, while squeezing your core and attempting to pull your belly button back toward your spine.
Do not let your hips sag or drop, if they do lower your body to the floor and begin again. The proper form is to maintain a straight line from your shoulders to your knees and hold in position for 20-30 seconds. If you are a beginner, hold for only a few seconds so that you can build good technique.