If you haven’t read the article by Bret Contreras, here are some facts about your glutes and hips that apply to your swing style and might help optimize power.
• Hip extension exercises that mimic vertical jumping have vertical or axial directional load vectors and include squats, deadlifts, and static lunges.
• Hip extension exercises that mimic sprinting have horizontal or anteroposterior directional load vectors, involve hip hyperextension, and include reverse hypers, back extensions, hip thrusts, pendulum quadruped hip extensions, and pull throughs.
• In resistance training, there are two distinct types of hip extension exercises; those that mimic vertical jumping and those that mimic sprinting.
• Hip flexor flexibility allows for hip hyperextension and is an absolutely critical component to maximum glute activation; tight hip flexors prevent hip hyperextension and maximum glute activation.
In the case of the swing, the consensus is that the motion resemble that of a vertical jump. But as we know, styles can vary, some swings can look like a pull through and almost like a forward leap more than a squat. By the way forward leaps without arm swing is a great assistance hip exercise.
So if hip flexor stretching helps vertical jump, we can assume it can help swings for some people with restrictions. This is sometimes seen in new beginners. Until they relax and get the technique they tend to stop the movement at the hips just a bit short of what it could be and rely on their arms to swing the bell.
This hip flexor stretch can be done just after your warm up. Remember that static stretching before training dampens signal for a muscle to contract. With kettlebell training, because we work mainly with extension, it is no problem for performance, and can potentially enhance it.
Same advice from Defranco, in his Fabulous 15 article.
Static Hip Flexor Stretch – In general, we’re not big fans of static stretching, especially before performing explosive activities. This stretch is a major exception. Try this. Perform a vertical jump and record the height. Then, static stretch your hip flexors – 2 sets of 30 seconds each leg. Really stretch the sh** out of them! Stretch as if you’re trying to tear that hip flexor off the bone, baby! Don’t just go through the motions! Now jump again. Chances are you’ll jump ½” – 2” higher, just by static stretching the hip flexors. Why is this, you say? We’ll tell you. You see, most athletes have super-tight hip flexors. When you jump, tight hip flexors cause a lot of friction, preventing you from fully extending at the hip, as well as reaching as high as you can. By static stretching them immediately before you jump, you not only stretch them out, but also “put them to sleep” do to the long, slow stretch. This causes less friction at the hip when you jump. This results in higher jumps. You will be amazed at how well this works. (By the way, the hip flexors are the only muscles you would ever want to static stretch before jumping.) It is also a good idea for athletes to get in the habit of stretching their hip flexors everyday, not just before jumping. This will help to increase your stride length when you run, as well as prevent hamstring pulls and low-back pain.
Any hip-flexor stretch will do but we will describe the one we use the most. Get in a lunge position with your left knee on the ground and your right foot as far forward as possible. Drive your hips as far forward as you can, while keeping your chest up. Try to get your left thigh 45 degrees to the floor. Raise your left hand as high as you can and twist slightly to your right, looking over your right shoulder and reaching over your head. You should feel a stretch in the left hip flexor as well as your abs. Perform 2 sets of 30 seconds and then switch sides.
If you have lower back pain or sciatica it could be related to trigger points in the hip flexor muscle. Before stretching the Psoas, it is recommended to address those trigger points.
Here’s a video that does that and show you a couple of stretches.
And a second video, very new age I admit. I like the use of the blocks to help proper alignment. But instead of blocks, we can actually put our palms on the bells.