Since the 1950s, rehab specialists have used proprioceptive neuromuscular facilitation (PNF) to lengthen shortened tissues and improve joint mobility.
PNF involves alternating between stretching the target muscle group and contracting the same muscle group while it is lengthened.
When using PNF to improve hip flexor length and hip mobility, you can begin by stretching the hip flexors of your right lower extremity by having it lengthened on the ground behind you while your left leg is in front of you, knee bent and foot flat on the ground. You can place your hands on the ground on either side of your front leg or on your front knee to help balance yourself. In this position, gently push your abdomen forward while keeping your lower back engaged – this position should stretch your right hip flexors behind you.
Once you are comfortable with this hip flexor stretch and feel you can handle a higher intensity stretch, you can bend your right knee behind you and hold your right ankle up close to your right buttock to further accentuate the stretch felt by your right hip flexors. Again, focus on keeping your lower back engaged and gently pushing your abdomen forward.
After 20 to 30 seconds of stretching your hip flexors, straighten your right leg behind you so that its only point of contact on the ground is the top of your right foot. In this position, actively push your right leg into the ground while keeping your entire right lower extremity as straight as possible – this is isometrically contracting your hip flexors while they are in a lengthened state. Hold this isometric contraction for 10 to 20 seconds. When starting out, I typically suggest using 20 percent strength, and over time, increasing to up to 80 percent.
You can alternate between stretching and isometrically contracting your hip flexors a few times. Over time, you will likely find that you can deepen your stretch after each period of isometric contraction.
Be sure to repeat all of the above for your left hip flexors, and maintain steady diaphragmatic breathing throughout the entire process.
You can use PNF to lengthen shortened tissues and improve joint mobility throughout your body. If you have any questions about this topic, please feel free to leave a comment below or send me a message at firstname.lastname@example.org.