Is Women's Flexibility a Liability in Yoga? Shari's Response to William Broad

by Shari

The latest New York Times article from William Broad Women’s Flexibility is a Liability (in Yoga) sparked a conversation between Nina and me, both whom are long-term yoga practitioners who have grappled with orthopedic injuries. Broad states that he has recently learned that women are at higher risk of hip injuries in a yoga class because of their inherent flexibility compared to men. He quotes a single yoga teacher, Michaelle Edwards, saying that “women’s elasticity became a liability when extreme bends resulted in serious wear and tear on their hips. Over time the chronic stress could develop into agonizing pain and, in some cases, the need for urgent hip repairs.” He also says of arthritis researchers:

The investigators found that extreme leg motions could cause the hip bones to repeatedly strike each other, leading over time to damaged cartilage, inflammation, pain and crippling arthritis. They called it Femoroacetabular Impingement — or F.A.I., in medical shorthand. The name spoke to a recurrence in which the neck of the thigh bone (the femur) swung so close to the hip socket (the acetabulum) that it repeatedly struck the socket’s protruding rim.

I personally can’t stand sensationalism of any type and particularly sensationalism of the fear and scare tactics kind. When I first saw this article, I groaned inwardly. But I then proceeded to read it carefully, including the related links, and then went on to do some additional research of my own. After all that, my response is: maybe.

First of all, I, as a long-term yoga practitioner, am not sure what exactly he means. We all can be overly flexible in some areas of our bodies and conversely overly tight in other areas of our bodies. The biomechanical model of structure and function is a beautiful yin and yang interplay between forces that influence our bodies, and yes, can ultimately change our structure and function. Some changes may not be as beneficial as others so we need to be consciously selective and astute to observe what changes occur with function.

I also think, as in the past, Broad is careless in his citations of his evidence and is vague about these ER records of hip injuries. However, he does cite some orthopedists and one international study that do substantiate his observation that women who put their hips into extreme ranges of motion can injure their hips. Well, this is blatantly obvious to anyone who may be neurologically intact. When a joint is taken into an extreme position there is a pain response recognized by the central nervous system that warns the person to back off. Of course, if we choose to ignore the pain response, then is it the yoga that is causing the injury or is it the person who is foolishly not listening to the feedback their body is providing?

I also think that to address William Broad’s assertion that women are more flexible than men, we need a better working definition of (biomechanical) flexibility:

Flexibility is the range of motion in a joint or group of joints, or, the ability to move joints effectively. Flexibility is related to muscle strength. Flexibility is also the ability to move through a full range of motion.

Flexibility is a conscious movement that has an intricate feedback mechanism between the muscles and the nerves innervating the muscles and the joints and the central nervous system. There are significant protective mechanisms that prevent the individual from overstretching if they PAY ATTENTION to the sensation of pain rather than ignoring it.

So are women “inherently” more flexible than men? Well, it depends who you ask. But all sports attract a body type, and if yoga is considered a “sport” then there is a body type that is drawn to yoga. We all like to do things that are “easy” and for some flexible bodies yoga is “easy.” The rub here is that this isn’t “yoga” but athleticism masquerading as yoga!

So now let us look at his assertion that yoga is the root cause of “femoracetabular impingement”. The literature that I read, including one of his references, states that the subjective symptoms are deep anterior groin pain with associated intermittent catching and locking of the hip joint. In addition, there is a significant decrease in hip internal rotation. The morphology is that there is a breakdown of the hip labrum (how the head of the femur is connected into the cup of the pelvic acetabulum) and the articular surfaces of the femur and acetabulum. There is a structural change in how the head of the femur is sitting and facing, and movement of the hip will continue to tear the tissue structures with a loosening of the integrity of the hip joint. The problem is that a lot of individuals who have this condition are pain free, asymptomatic and don’t know they have it. The concern is that this condition may be a precursor to developing hip arthritis down the road. There are four types of femoracetabular impingement and one type is more common in women and one type more common in men!

Another article that I read stated that the condition is caused by internal rotation of the hip while in 90 degrees of hip flexion. Yes, this can be Uttanasana (Standing Forward Bend)! So is the problem the combination of these two movements? I don’t know, but does that mean you need to stop doing Uttanasana? I don’t think so unless it is causing pain. And, yes, there are some pretty extreme hip positions in yoga which only some of could do when we were younger (maybe can still do them now) but the bottom line is that we need to practice with intention and attention to form, function and our own bodies' abilities and not soldier on through the pain. Yoga, as we have mentioned time and time again, can be physically and mentally challenging, but is not supposed to hurt. So don’t be scared off again by a sensational journalist who claims he is a yogi.

In a future post I would like to present some of the inherent differences between male and female pelvis and hips that might also help to put into perspective the allegation of the differences between men and women.

How Much “Stretch” is the Right Amount?

by Baxter

Last week I looked at the concept of “compression” both as a perceivable event in your body and as a potential problem for your body when doing asana (see Tension Versus Compression). After that post, one of our readers requested information about the other sensation producer, muscle tension, and the usually desirable event that occurs when we do asana, stretching in the muscle.

In the vast majority of our yoga classes in the US, we are continually asked to notice the sensations arising from the various yoga asana as we perform them. We are encouraged to find our “edge,” a place or perception of muscle stretch before which we don’t feel much, and beyond which we feel too much or begin to encounter pain. We are led to believe that stretching our tight muscles is highly desirable, but often are not clearly told where the “finish line” of this process might be. So how much stretch is the right amount? How much is too much? And how can we tell the difference? I have an opinion on all of these questions, but I took a look around to see if there was any objective evidence that might give more credence to my opinions.

The first interesting article I came across was How Necessary is Stretching? a New York Times article from 2009. Here Gretchen Reynolds reported on at some new information about stretching that had just been discovered. One study looked at a group of runners at a university in Nebraska. Researchers measured the runners' hamstring flexibility, then compared hamstring flexibility to a measure of their success as runners (known as “running economy”). They found that runners with tighter hamstrings were actually faster and stronger runners. Reynolds noted that, “In fact, the latest science suggests that extremely loose muscles and tendons are generally unnecessary (unless you aspire to join a gymnastics squad), may be undesirable and are, for the most part, unachievable, anyway.” She went on to quote a sports medicine expert:

“To a large degree, flexibility is genetic,” says Dr. Malachy McHugh, the director of research for the Nicholas Institute of Sports Medicine and Athletic Trauma at Lenox Hill Hospital in New York and an expert on flexibility. You’re born stretchy or not. “Some small portion” of each person’s flexibility “is adaptable,” McHugh adds, “but it takes a long time and a lot of work to get even that small adaptation…””

This made me consider what purpose my yoga “stretching” was for. I tend to think that stretching is going to give me more success and less discomfort in performing my asana. The above article did mention one benefit of a regular stretching of the muscles. If done regularly, even if the length of your muscle does not change much, your perception of the intensity of the stretch sensation diminishes. In other words, you don’t feel so tight anymore. So stretching regularly will make your asana more comfortable, and if you are practicing asana to prepare for seated meditation or pranayama, you will also find it easier to sit comfortably on the floor.

Reclined Leg Stretch

For healthy aging, stretching is important for maintaining flexibility as you age. Without regular stretching, your muscles will become stiffer, potentially interfering with your ability to go about the normal activities of daily life, including dressing yourself, driving, walking unassisted and even getting in and out of a chair (see Transferring and Yoga), and can impact your ability to balance. For all these reasons, stretching is very beneficial for you whether or not your muscles actually become more flexible.

Before I go much further with that train of thought, let’s look at what else I found. When a muscle is stretched, it not just the muscle cells themselves that do the elongating, but also the connective tissue or fascia that surrounds and penetrates each muscle of the body. Where the muscle has pretty amazing ability to elongate and contract and change size dramatically, the ability of the fascia is more limited, even when it contains some elastic cells. And when the connective tissue is over-stretched, it can lose its supportive properties for the muscles and lead to increased chance of the muscle itself getting micro-tears that heal more slowly. In addition to the fascia, the other connective tissues, such as the tendons that attach the muscle to bone, are more vulnerable to injury as well.

So, I think common sense regarding stretching muscles is to work up to a point discomfort, but not into frank pain. Try to get the sense of stretch in the center of a long muscle and try to avoid sensation closer to its bony attachment at (or near) the joint.  On occasion, you will know you have overdone it by the sudden quality of pain that accompanies your stretch, but often you won’t know until the next day, when inflammation sets in and the pain is there more persistently. Shoot for taking your stretches slowly and mindfully, keeping your personal goals in mind as you work in your poses.

And as Paul Ingraham points out in The Unstretchables: Eleven Major Muscles You Can’t Stretch, No Matter How Hard You Try, some muscles aren’t actually stretchable the way muscles like the hamstrings—which are quite literally made for stretching—are. I know there are a lot of thoughts on this topic out there, so feel free to add your insights here. I believe in our collective wisdom!

Friday Q&A: On Your Feet All Day

Q: I liked the comments on flexibility (see Flexibility and Aging).  I would love it, since you addressed the couch person or the sitting person, if you could address the person that stands all day. Is on their feet all day.

A: The area that gets tight from standing is your low back. So any type of back-bending is good for counteracting a day spent on your feet. You can do conventional backbends or even bend over the edge of your bed, a table or a counter (the way you back-bend over a yoga horse). Seated forward bends may also help relieve your low back.

Stretching your hips (external rotators) is also helpful, so try the standing twists as well as the seated Marichyasana variations. After you release your hips, you may want to work on your legs. You could try standing lunges with your arms up the wall (a modified Warrior 1 pose). Standing Padangusthasana also works well for this. Any type of calf stretch is also good. Basically, any standing pose will help counteract the static position of standing all day. So how about Triangle pose (Trikonasana), Extended Side Angle pose (Parsvakonasana), and Intense Side Stretch pose (Parsvottanasana)?

—Shari

A: Because your hips and legs get tight from standing, Baxter recommends his dynamic leg stretch and hip opener series (see Dynamic Reclined Hip Stretches). Lying on the floor as your stretch your legs and hips will relax your lower back at the same time as you encourage the blood to flow back toward your torso from your legs and feet (which is helpful if you have any swelling).

My favorite way to stretch my legs and rest my back after spending a lot of time on my feet is to practice the Reclined Leg Stretch series (Supta Padangusthasana) followed by an inverted pose, such as Shoulderstand on a chair or Legs Up the Wall pose (Viparita Karani). The inverted poses use gravity to stretch your legs (how cool is that!) at the same time they return the blood back to your torso, reducing swelling in your feet and ankles.

Because the tightness in your torso, shoulders, and neck is the similar to that created by sitting all day, the two poses Shari recommended for counteracting sitting will also be very helpful for standing (see Flexibility and Aging).

—Nina

Flexibility and Aging

by Shari and Nina

Shari and I have talked in the past about how essential it is to maintain strength as we age (see Strength and Aging), but I’ve learned from her that it’s equally essential to maintain our flexibility. I thought today I’d talk with her about this important topic. —Nina

Nina: Why is it important to work on flexibility as we age?

Shari: This question kind of has a long answer because we need to define flexibility and how it might change as we age. The first thing is that as we age we tend to only do things we like to. There isn’t anyone telling us to “stand up straight” or go for a walk or do something other than lay on the couch! I am sort of exaggerating but the truth is that we tend to have habitual postures, and if we don’t reverse these postures often during the day we end up looking like what we do all day. If you sit in a soft sofa or recliner chair all day long when you finally decide you WANT to stand erect, you might not be able to because certain muscle groups have shortened from habitual posture! Also, the adage “use it or lose it” really is true in regards to flexibility. So if you want to continue to be mobile and independent as you age, maintaining flexibility is as important as maintaining strength.

So what should the couch potato do to counteract their sitting posture? Stretch those hips, upper and mid and low back! Move those arms and legs! See yoga does affect our flexibility. But why? When we perform asana, whether it is active or more passive like supported restorative poses, our muscles are often lengthened. We know this intuitively because when we stretch TOO much, we pull back and come out of a pose (at least that is the safe and healthy way to practice asana). But we can also intelligently approach stretching in asana by understanding some fundamental spinal cord reflexes all of us have, at least those of us who are ambulatory with four limbs moving in space.

There are three main spinal cord reflexes: the stretch reflex, the autogenic inhibition, and the reciprocal inhibition.

The stretch reflex is a specialized reflex that regulates the length of your muscles. Whenever you elongate a muscle beyond a certain preset length or unconsciously stretch it too fast, this reflex makes the muscle automatically contract so you can’t lengthen it any further. The stretch reflex is governed by a long thin receptor in the muscles called a muscle spindle. The spindle’s role is to let our feedback systems know about muscle length and the rate of muscle lengthening. When a muscle is rapidly stretched, the spindle (via a loop of nerves) triggers a reflex contraction of the muscle that is undergoing the stretch and this muscle contraction limits the stretching of the muscle.

Within the muscle tendon (which attaches muscle fibers to bone) are structures called Golgi tendon organs (GTO). The GTO’s are stretch sensors, which provide the central nervous system with information on muscle tension. When a muscle is either contracted or lengthened (stretched), this information is processed by the central nervous system. The central nervous system then tells the muscle to release and be inhibited from contracting or to relax and lengthen. This autogenic inhibition protects the muscle from tearing.

The muscle spindle is also responsible for a phenomenon known as reciprocal inhibition. In this case when a muscle contracts, the opposite muscle will relax to allow the movement to occur without resistance. An example here is when you straighten your leg, the quadriceps muscles cause the knee to straighten, but for this to occur the hamstrings on the back of the leg/knee must relax or release at the same time.

We can perform static stretches where our body’s joints are positioned in their outer limits of available range and hold these positions for a certain time, this activity becomes a continuous passive stretch. This type of stretching is typically safe because we don’t go further than we are able. In this type of stretch the connective tissue and the non-contractile tissue is lengthened because of its unique structure. Muscle tissue is called viscoelastic because it CAN lengthen and then return to it’s “resting length.” This is basically what we are doing in asana. AND if we hold a pose for more than 6 -20 seconds, we can stimulate the autogenic inhibitory reflex to trigger a relaxation in the muscle.

If you are interested in a scientific approach to stretching, get Ray Long’s anatomy and asana books for clear through pictures and direct relationship to asana practice. He has six books and you can find them on Amazon. Also, see Fernando Pages Ruiz’s article What science can teach us about flexbility in Yoga Journal March April 2000 issue.

Nina: Which are the most important areas to target for maintaining flexibility as we age?

Shari: How about the entire body? Honestly, I can’t think of any area that should be neglected if we consciously stretch. Of course, we all think about our legs (hamstrings) and hips (hip flexors), but what about keeping mobile ankles and feet and hands? Think about all the arthritic changes that happen in our hands and feet as we age. Also, our spines absolutely need to be maintained to perform full range of motion for flexion, extension, side-bending and rotation. Our activities of daily living aren’t enough and we need to MOVE out of our habitual postures.

Nina: It’s true that most people think about their legs being stiff and maybe their hips, but not so much about their spines, shoulders, feet, ankles, and hands. So what are you favorite poses for maintaining flexibility?

Shari: My favorite poses for maintaining flexibility would be Downward-Facing Dog pose and Purvottanasana (Upward Plank pose). I think of these two poses going together, with the back body being stretch in Downward Dog and the front body in Purvottanasana. Shoulder flexion is nicely addressed in Dog pose and shoulder extension in Purvottanasana. 

And, of course, backbends are important for stretching the muscles that get tight from typical seated positions. Passive backbends are good because they don’t take as much muscular effort as Upward Bow pose (Dhanurasana). In an ideal world we should practice our flexibility poses daily. We could do both Downward Dog pose and Purvottanasana for 30 seconds. Then, if we were on a roll, we could add Triangle pose (Trikonasana), and Extended Side Angle pose (Parsvokonasana). Simple and effective!

Nina: What a great mini practice! Both Downward-Facing Dog pose and Purvottansana are also excellent for building upper body strength. Most people practice Downward-Facing Dog pose on a regular basis, but I think Purvottansana is often overlooked and under-appreciated. Thanks for reminding us about what a valuable pose it is.