The right way to stretch your hip flexor [video].
Most people attempt to stretch the hip flexor incorrectly by moving too far forward and arching the low back too much. If this is you, watch the video. The key is the setup.
Pullthroughs - a better way? [video]
This is a great alternative if using some attachment for the hands increases back pain or you find yourself pulling too much with the arms. Start by setting the pulley so it is around hip-height. Set the strap so it goes around the front of your hips. Set and brace your neutral spine position. Focus on keeping pressure through the heels and sitting back through the hips. To return to the start position, squeeze the glutes and push the hips forward. Avoid overextending the hips and straightening the body as this will cause you to lose your balance and fall back.
Spiderman stretch [video].
This is an excellent movement for mobilizing and stretching the hips. Start with the first position and progress to the others as needed. Remember, focus on a mild-to-moderate intensity in the hip and glute area when performing these. Start in a pushup position. Bring one leg forward to the outside of the arm. In the second video, bend the elbow and try to get it as close to the floor as you can. In the third video, rotate the arm up towards the ceiling. Make sure to rotate the body, not just the arm. One way to help do this is to keep your eyes on your hand. The arm should not travel where the eyes cannot follow it.