Strengthen and balance your entire body with this powerful standing pose.
Jānuśīrṣāsana is a seated forward bending pose that gives a deep stretch to the back and legs. The name comes from the words jānu, "head," and śīrṣa, "knee," and is often translated as "head to knee pose."
Stretch the back, hips and legs
The combination of sitting and bringing one leg into external rotation places more emphasis on the stretch in the lower to mid back. The asymmetrical nature of the pose allows students to work with one side of the back/legs/hip at a time.
Move the apāna vayu region
This deep forward fold moves the lower abdominal area (associated with removal of waste and impurities).
How to do jānuśīrṣāna:
- Begin seated in daņḍāsana, with both legs extended straight in front and arms by your side. Maintain jālaṁdhara bandha throughout the entire sequence.
- Bend the right knee and turn knee out to the side, placing the foot on the inner left thigh. Turn slightly toward the left leg.
- As you inhale, raise both arms up from the front until they are alongside the head.
- Exhale as you bend forward, extending the spine over the left leg. At the end of the forward fold, lower the hands toward the floor beyond the left foot and clasp the left wrist with your right hand.
- Sthiti going in to the pose: Inhale, keeping hands clasped around foot, extend spine fully. Exhale, and bend more closely to the left leg.
- Sthiti moving out of the pose: Inhale, keeping hand clasp and spine extension, allow breath to lift torso away from the leg a bit. Exhale, fold toward leg, but not as completely.
- Inhale and raise arms alongside head, extend upper back and return to upright position.
- Exhale and lower arms.
- When one side is complete, bring right knee back up and straighten next to other leg. Then repeat on other side.
Posture can be done dynamically or with a stay.
Tips and Modifications
The trick of this posture is to keep the extension of the spine and maintain jālaṁdhara bandha for the entire forward fold; these elements are fundamental to the posture. Concentrating on exhale technique (drawing the lower abdomen toward the spine on exhale) as you fold forward will help keep the spine and head in position.
Since jānuśīrṣāsana requires so much back, hip and leg flexibility, most students will need to modify the pose by bending the knee of the straight leg and/or raising the hips. Use a folded or rolled blanket under the knee or hips accordingly.
Students can place their hands alongside the extended leg instead of the handclasp.
For some students, bending the knee and bringing the hip into external rotation is impossible or strains the hip, knee or ankle. For those students, I offer the modification of just bending the knee and keeping the foot on the floor (but walking the foot out a bit so there is space to fold forward)--this modification ends up looking like maricyāsana.
Another version I like is to sit with both legs straight, but with feet about hip width apart. Then the student folds forward over one leg at a time. The wide-legged forward bend, upavistha konasana, might be another good option for stretching the back, hips and legs, without requiring the external hip rotation and knee bend.
However, if a student is unable to comfortably sit in the starting position for this pose, I am concerned that a seated forward bend may not be appropriate, and I would prefer to give the student a more useful forward bending posture, like vajrāsana forward bend (child's pose) or apānāsana.
Primary Muscle Actions
- Erector spinae, gluteal/external hip rotators, groin and leg muscles are stretched.
- Upper back, lower back and shoulders/arms are strengthened to some extent.
- Stretches back, hip, legs and groin.
- Strengthens upper back.
- Compresses abdominal area (apana region) and has a "cleansing" effect, especially when paired with exhale technique of drawing lower abdomen up and in toward spine.
Take care of hips and knees in this pose. Do not use any sort of force to place the foot on the inner thigh.
Utkatasana, or chair pose, is a standing forward bend that lowers the hips toward the heels into a low squat. This pose asks for a lot of strength and flexibility, which makes it challenging for most students.
Stretch the Lower Back and Hips
This low squat pairs gravity with full hip flexion to completely lengthen the lower back, especially in the classical form of the pose, in which the legs are together and the arms are extended overhead, which prevents the legs and upper back from compensating for any stiffness in the lower back.
Strengthen the Legs
The legs, especially the gluteal muscles, use a lot of power to press the body back up to standing. This makes utkatasana a good choice for building strength to prepare for staying in difficult standing poses.
Finding the Pose
- Begin standing in samasthiti, with legs together and hands by your side. Set jalamdhara bandha.
- Interlace the fingers and turn the palms out, away from your body.
- Inhale and raise the linked arms overhead so that arms are outside ears and the palms are facing the ceiling.
- Exhale and begin to sit hips down toward heels, maintaining jalamdhara bandha and keeping spine as vertical as possible. Arms remain extended overhead.
- Inhale and extend upper back and arms as you return to standing.
- Exhale and lower arms. Release hands.
Tips and Modifications
Utkatāsana is very physically demanding. Most students won't be able to begin to lower the hips into a squat without bringing the feet wider (up to hip-width apart) and having the arms either in a wide "V" shape or lowering the arms as they exhale and lower the hips.
Many students will also need a folded or rolled blanket under their heels to compensate for lower back tension, especially in the beginning.
If students are straining in this posture, I often give them uttanāsana or vajrasana forward bend as an alternative that will lengthen the lower back and still build some leg strength without being quite so demanding.
In Ashtanga yoga, utkatāsana is often practiced with a back arch and on an inhale. This is referred to as ardha utkatāsana and considered a backward bending posture in the Krishnamacharya/Desikachar tradition.
Primary Muscle Actions
- Erector Spinae, Gluteal and Leg Muscles are strengthened.
- Lower Back erector spinae and gluteal muscles are lengthened.
- Depending on arm movement chosen, arm and shoulder muscles may be strengthened to maintain extended position.
- Lengthens lower back.
- Strengthens entire back and legs.
- Compresses abdominal area (apana region) and can help balance this region if not too intense.
For students who have knee, hip or lower back injuries, and especially if these joints are inflamed, stiff or causing pain, utkatāsana is too intense. I suggest uttanāsana, vajrāsana forward bend (child's pose) or apānāsana as a safer option. For pregnant and menstruating students, I would suggest the same alternative.
Ankle injuries seem to be aggravated by this posture as well. Proceed slowly and with caution.
Uttānāsana is a standing forward bend that stretches the entire back of the body, from the bottom of the feet to the back of the head. It is a deceptively simple form--bending at the hip with the hands by the feet--but it's simplicity lends it to many adaptations.
Primary Functions of the Pose
Lengthen back of body
Flexion of hips and spine gently elongates the muscles of the entire back as well as the hips and legs. Lifting the arms also lengthens muscles around the chest and shoulders.
Strengthen the upper back
A lesser known benefit of uttānāsana is the incredible upper back strength the posture builds. This makes it a great preparation for lengthy seated practices like chanting, pranayama and meditation.
Compression of the lower abdomen while exhaling has a soothing, lightening effect as it moves the apana region, the area responsible for elimination. This can help digestion, elimination of waste and quality of breath.
Finding the Pose*
1. Begin standing with feet together and hands at your sides.
2. Set jalamdhara bandha,** in which you lengthen the back of the neck by inhaling, then setting the head slightly back and dropping the chin a bit toward the chest.
3. On an inhale, raise arms up from the front, so that arms come up alongside ears with palms facing forward.
4. On an exhale, draw lower abdomen toward spine and fold upper body over legs, maintaining jalamdhara bandha and length in spine.
5. Inhale, lift the arms and the upper back, extending through the spine as you return to standing with arms overhead.
6. Exhale, lower your arms by your sides.
*These instructions are the "classical" version of the posture, and they require a lot of training, flexibility and strength. Almost all students will need some of the modifications below, especially when starting out.
**I'll post more on jalamdhara bandha next week!
Tips and Modifications
Students will often need to modify this posture to compensate for tightness in the lower back by bringing their feet up to hip-width apart and/or bending their knees as they fold forward. On the other hand, very flexible students may need to keep their feet close and concentrate on drawing the belly in on the exhale to help lengthen the lower back. Teachers should look for movement happening in the lower back (the lower back arch should round out), and little to no rounding in the upper back.
Especially in the beginning, most students will need to bring arms quite a bit wider (in a "V" shape) as they inhale to allow more movement in the upper back. There should be a feeling of spaciousness as the arms lift overhead. If students feel strain when lifting the arms overhead, another option is to let the hands slide down the legs toward the knees or ankles as they fold forward. For students with neck strain, I often have them use one arm at a time, or keep arms by their hips, with fingers extending away from the head, to gently build some upper back strength without agitating the trapezius muscles.
Uttānāsana is often taught with the arms sweeping in a wide arc out to the sides on the way up and down. This movement of the arms removes some of the upper back strength and flexibility needed to do the full posture, which is often useful. But it also takes away some of the length in the lower back, and students may not achieve as much benefit from the posture.
One of the tricky but critical parts of this pose is coming back up with the upper back in extension, rather than rounding forward. Rounding in the upper back puts strain on the lower back and hips, and also misses the strength-building piece of the pose which makes it such a good preparation for standing and seated postures. It also restricts breath capacity on the inhale, which for me is the most transformative piece of this posture. When there is space for the inhale to really expand, the entire posture seems to just grow from inside. Body and mind are uplifted, and the pose becomes invigorating and refreshing--it's a perfect preparatory movement for practice. Without the extension in the upper back, it feels like slogging through dull work, with a little back stretch in the middle.
Here's a tutorial to highlight the upper back movement in uttānāsana:
I find that practicing the seated version of uttānāsana makes the posture "easy enough" that I can actually experience it, not just push through it. It gives me opportunity to feel the lengthening in the lower back on the way down, and the strengthening on the way up, and to work at a speed and range of motion that is well within my capacity. Then I can apply what I've learned to the standing pose.
Classically, uttānāsana is practiced with a "sthiti", or a short stay, on the way in to the pose, as well as on the way out, as a way to prepare for and to release the posture. For sthiti into posture: Inhale, allowing inhale to extend spine still further. Exhale, and fold forward as much as you can while keeping upper back long and neck in jalamdhara position. For sthiti on the way out: Inhale, letting breath extend the spine (it will lift your upper body out of the posture a bit). Exhale, bending forward, but not quite the entire way.
Primary Muscle Actions
- Lengthens erector spinae, as well as quadratus lumborum, gluteal muscles, hamstrings and gastrocnemius.
- Strengthens erector spinae, gluteal muscles and posterior neck muscles.
- Depending on choice of arm movement, can lengthen pectoralis muscles, trapezius and latissumus dorsi, and strengthens latissimus dorsi, deltoid and rhomboid muscles.
- Lengthens entire back of body.
- Strengthens postural muscles of upper body.
- Compresses abdomen on exhale--moves apāna region.
- Improves quality of exhale, which creates space for inhale, and helps digestion and elimination.
Especially for students with back injuries or recent back surgery, proceed with caution. Students who come to yoga for flexibility often remark that they want to touch their toes, and may push (or pull) into deeper versions of this pose before their bodies are willing. The movement of this pose originates from the breath, and should be strong, but also steady and contained.
If students are not able to do standing uttānāsana with strain or pain, I teach them a seated version. If the seated version is still too much, we focus on floor poses (like apānāsana) and breathing.
Students with hip or knee injuries also have difficulty with bending forward without pain in this posture, and I usually recommend a seated or lying down forward-bend in that case as well.
I have heard that having the head below the heart is contraindicated for students with glaucoma, but I've also heard that the change in blood pressure to the eyes is insignificant when bending over. If this is a concern for you, I recommend talking to your doctor for professional medical advice.
How to bend forward without stressing the spine (by Olga Kabel at Sequence Wiz)
Vajrāsana Forward Bend, more often called Child's Pose, is a soothing and quieting posture for the mind and body. The forward-bending components are relaxing, and the pose can build flexibility in the back to prepare for deeper forward bending poses. It's an excellent counter-pose as well, as the movement of the back, hips, shoulders, legs and and arms can relieve strain and improve function in all these areas.
Functions of the Pose
Lengthen back of body
Flexion of hips and spine gently elongates the muscles that run along both sides of the spine as well as the outer hips, buttocks and hamstrings. Especially for students with chronic low back pain, this gentle movement can gradually relax the back muscles, preventing strain or overstretching in these tissues.
Compression of the lower abdomen while exhaling has a soothing, lightening effect as it moves the apana region, the area responsible for elimination. The apana-pacifying quality also improves digestion, elimination of waste and quality of breath.
Finding the Pose
- First, come to hands and knees, with knees under hips and wrists under shoulders.
- As you exhale, allow your hips to drift toward your heels, so that the weight of your body moves toward your legs and you feel the lower back lengthen.
- As you inhale, return back to hands and knees, using the strength of the upper back and legs to lift, and gradually placing weight back in the hands.
- Move this way with your breath. You can also stay in the exhale position (child's pose) for a breath or more as you warm up to it.
Tips and Modifications
Many students will feel more comfortable in this pose if they bring the knees or hands slightly wider to borrow mobility from the hips or shoulders. This can be especially useful for students with less mobility in the spine. However, students should not bring the spine into extension, curving toward the floor, as that can increase the load on the mid and lower back.
Most students will need some sort of cushion under their knees to protect the joint. Students may need extra cushion or need an alternative to this posture if pressure on the knees is contraindicated. I generally utilize vajrāsana forward bend for the lower back and hip movement, and if students need an alternative I have them do uttānāsana in a chair or apānāsana to get a similar function.
Another method of entering and leaving this posture is to begin in vajrāsana, seated kneeling on the heels. On the inhale, stand on the knees and lift the arms overhead. On the exhale, hips move back toward heels as hands move out in a wide arc and meet together on the lower back or on the floor outside the legs in the child's pose position. This method requires more strength in the legs and upper back, as well as more flexibility in the back
I typically use vajrāsana forward bend as a counter-posture, to relieve strain from a long period of standing poses, or after backward-bending postures like bhujangāsana (cobra) and salabhāsana (locust). The hands-and-knees position also makes this pose a great transition from standing to the floor and vice-versa.
Vajrāsana forward bend is part of the vinyasa krama for cakravakasana, a backward-bending posture in which students extend one leg (and possibly the opposite arm) to lengthen the body. The combination of cakravakasana and vajrāsana forward bend is a great preparation for more challenging backward-bending postures.
A note about "cat-cow" pose in yoga: Many styles of yoga make use of a movement called cat-cow, in which the student is on hands and knees and alternately moves the spine through flexion (rounding like an arch) and extension (dropping the waist toward the floor). I have found that this movement has little real benefit and carries lots of opportunity for strain in myself and my students. This movement increases compression of the low back in the "cow" shape and increases the rounding of the upper back in the "cat" shape; most students will find greater benefit with emphasis on lengthening the spine, not just bending it. I teach the above variation of vajrāsana forward bend because I find it brings more movement where needed and doesn't increase the strain on already taxed areas of the spine.
Primary Muscle Actions
- The erector spinae, hamstrings, gluteal muscles and outer hip muscles (piriformis, etc.) are gradually lengthened as the hips settle toward the heels.
- Trapezius and rhomboid muscles relax as weight is removed from the arms, and the lattisimus dorsi muscles are gently lengthened as the hips move back.
- The glueteal muscles, outer hip, hamstrings and erector spinae (especially in the upper back) are strengthened when returning to the starting position.
- Stretches back, hips and legs and provides relief from lower back pain.
- Reduction of stress, tension and anxiety.
- Overall feeling of release, safety and composure.
- Can help relieve menstrual or digestive discomfort.
For some students, including many with disc herniation or spinal stenosis of the lumbar spine, flexion of the spine (and sometimes of the hips) is contraindicated. Apanasana may be more suitable, but students should be certain to move slowly and only at the hip join (their lower back shouldn't curl up off the floor).
Although the knee flexion of child's pose can be therapeutic for knee injuries, students with history of knee problems or recent surgery should take care not to push into the posture. There should be no sensation of stretching or pain on the ligaments surrounding the knee. If full knee flexion isn't attainable, students can think of only moving hips back a bit to lengthen the spine, not down toward the heels. Likewise, students can place a rolled blanket underneath their ankles if extension of the ankle joint is uncomfortable.
During the mid to latter portion of pregnancy, when abdominal pressure is contraindicated and uncomfortable, students can try a wider-kneed child's pose.
"Magic three yoga poses and how they can make you feel better every day" (Olga Kabel at Sequence Wiz)
"Chakravasana" (video includes vajrasana forward bend and adho mukha svanasana, downward dog)
One of the most interesting and practical things I've learned in the viniyoga approach to teaching classes is how to modify various yoga tools. From yoga poses, to breathing patterns and meditation, all the pieces can be adapted to the different needs of individuals, or to a theme you might choose for a group class.
Learning how to modify yoga poses is crucial for teachers because group classes usually spend more time on asana than on other parts of practice, and modifications make poses more safe, effective and meaningful. Plus, if you're just starting out with adapting yoga to different needs, it's easiest to begin with yoga poses, because they are tangible, visible things that can be understood at a gross level.
When you are modifying any yoga tool, the key idea to keep in mind is that these tools have function. There are really no rules, and the lists of alignment principles (knees over ankles, arms shoulder-height, feet 3 1/2 feet apart and parallel, etc) can be thrown out the window, as long as you and your students are paying attention and preserving the function of the chosen yoga pose.
Begin by defining what function you are hoping to achieve, choose movements and modifications that you anticipate will get you there, and pay attention to the students as they practice so you can guide them and change things as needed.
From a wide-angle view, here's how you can modify yoga poses:
These days, most people associate yoga with increased flexibility, and yoga poses are certainly a very useful tool for changing patterns of movement. Most yoga poses are designed with the idea of lengthening in mind--forward-bending lengthens the back of the body, for example, and lateral-bending lengthens the side.
As you are planning your class, think about what areas of the body you want to create the feeling of movement in. This depends on the overall purpose of your class and your specific population.
If you've observed that a student has lower back stiffness, you might have him change the position of his feet or bend his knees in a forward-bending pose, so that you can bring a bit more movement to the low back. You could have him sit on a chair or bolster to give the back more freedom in seated poses.
If you notice your students have shortness of breath, you might create more room for breathing by having students lift their arms wider so the rib cage moves more freely. Or you could emphasize forward-bending postures that move the abdomen in on the exhale to encourage a fuller breath.
Of course, yoga poses are not only about increasing flexibility. Most students in group classes will need some focus on developing strength as well. In fact, the people attracted to yoga class and bendy poses most likely need the strengthening aspect.
Take care not to confuse strength with strain, though. You don't want your students to be pushing or forcing their bodies past the boundary of what is safe for them. The same is true in regard to flexibility. Help them find a steady balance where the breath flows smoothly. (This is the concept of sthira-sukham-āsanam, Yoga Sutra 2.46.)
You'll find that most students are disconnected from their strength in at least some areas of their body. Look for the areas that move too freely or seem to collapse--perhaps the shoulders, or lower back, or wrists. Those are the places that can use stability. You can modify yoga poses to give students the experience of what strength or stability feels like in the areas.
You can think of increasing stability as restricting movement. So for students whose lower backs arch excessively in virabhadrasana, a focus on lengthening the tailbone down will stabilize the lumbar spine. For hypermobile shoulders, interlacing fingers when bringing the arms overhead will restrict shoulder movement and encourage upper back strength. In standing poses, changing the width of the feet can restrict movement in the hips, legs and ankles and build strength.
Stability can also come from an outside source, and using a prop can help build a student's connection to inner strength. You might have your students place their back heel against a wall for added support in virabhadrasana or parsvottanasana. Or have students place a hand or fingertip against a wall in balancing poses.
Once your students have a feeling for strength without strain, then you can build and challenge it. You can remove common props, and have your students to try standing poses without a yoga mat. And you can introduce longer stays in poses that require strength.
A more subtle way of modifying yoga poses is to cultivate a particular attitude in them.
Give it a try:
- Sitting as you are, take 5-6 breaths with your shoulders rounded forward, just to see what that feels like.
- Then take several breaths with your shoulders in a neutral position.
- Then in a rolled back, military-style position.
Notice the difference in how you feel in each posture. By adopting a different "attitude" in your shoulders, you can influence how you feel, and even how you think.
Gestures are ways that your body communicates to the outside world, but they also leave an imprint on your mood and memory. Smiling, for instance, not only communicates joy or friendliness to others, but it lifts your own mood as well.
By incorporating simple, subtle gesture into yoga poses, we can bring the effects of the practice to a deeper level. It can be the subtle difference between turning palms up or down in a seated position, or bringing your hands over your heart while resting instead of to your lap or your sides.
Take some time to observe yourself and others, and you'll notice so many gestures and small movements that say a great deal about what the person is feeling and thinking. You can begin to incorporate gestures into yoga poses to evoke the feeling.
Just be sure to keep it subtle. Let your students feel what they feel. Don't try to control it by telling them what they are supposed to feel. If you are asking them to open their arms out to the sides as they breathe in, don't say they are "opening their hearts to possibilities." Let their experience speak for itself. Learning is much deeper when it comes from personal experience and inner wisdom, rather than an outside source.
There are many other ways you can modify a yoga pose. You might use a visualization, or bhavana, to influence how your students do and feel a movement. You could ask your students to imagine moving through water, for example, to help them move more slowly and fluidly, or you could have them imagine a rising sun, or a full moon, or a mountain. As with gestures above, an image or idea can create different attitudes in movement, and it impacts the rest of your system.
You can use story and myth as well. One of my teachers began a class by telling a story about Ananta, the great serpent, to illustrate the concept of sthira/sukha. The image of the soft, heavy coils of the serpent's body and its strong, protective hood rising up was a powerful tool in communicating the idea of ease and stability.
Breath is, of course, a wonderful way to influence the effect of a yoga pose. It can be as simple as just noticing the breath, or imagining the breath move into or out of the body in a certain pattern. You could have students begin breathing just before the movement starts, so that the movement grows from the breath. Or students could count different parts of breath as they are moving or staying in a yoga pose.
I love introducing chanting or mantra in yoga poses. You can use a simple word or phrase (in Sanskrit or English) and ask the students to say it in their minds each time they come into the pose. Even just making a soft sound like "ahhh" brings the students to a more focused practice.
There is no end to ways you can modify yoga poses to make them a more personal and meaningful experience for your students, and to make them more than goals to reach, or an exercise to get through. Yoga poses have potential to enrich and harmonize the lives of your students. The teacher's role is to understand how they work, to see the impact they are having during practice, and to shape the practice and poses to serve their students best.
Most of my new students arrive at yoga class ready to exercise.
They are ready to stretch, to balance, and maybe sweat a bit, so they can change, or fix, or maintain their bodies.
Then I ask them to breathe.
Over and over, I ask them to breathe. Finally, we move a bit, but I ask them to move slowly, or gently, or gradually.
This is not something most adults are used to doing. Especially in an exercise class.
But I wouldn't insist on it so strongly if it didn't work so well.
You see, yoga is not like other types of physical exercise.
Or it least, it ought not be, because it was designed to work differently. Yoga is about being able to direct the mind, because great change is possible (inevitable, really) when our perspective is cleared.
And as far as yoga is concerned, the mind and body are linked together so strongly, that moving and placing the body in a specific way is a very good preparation for meditation.
Patanjali's Yoga Sutra gives the properties of yoga postures:
Posture (āsana) is steady (sthira) and comfortable (sukha). Yoga postures have support and adequate strength, and they do not create pain or exacerbate medical conditions.
It is a perfect balance of effort (prayatna) and effortlessness (śaithilya) combined (bhyām) with complete and endless (ananta) concentration (samāpatti).
This feeling of perfect balance is so different than what we do in exercise and other physical work.
In exercise, we are encouraged to push beyond our limits, to lift one more, run faster or farther, and to get the job done. It's a test of will to overcome your physical limitations.
But will and tenacity can be misguided. They are directed by the ego, and can drive you full-speed in directions that you thought you wanted to go, but end up bringing you frustration or pain, upset your life or relationships.
I'm not denigrating exercise or physical fitness. But yoga is in a different category of activity. It's in the business of helping you see clearly. And letting you perpetuate habits of overworking, overcompensating or avoiding conflict is not in the program.
In my own practice, sthira-sukha is the absence of certain habits.
There is no setting of my jaw, no determination to achieve or prove something, and there is no reaching or pulling further. It feels like there is an internal engine giving me purpose and strength, but it's not willpower. It's a steady, feeling, quiet focus.
When I teach, I see too much sthira when my student's faces become hard around the corners of their eyes and lips. Their body language becomes rigid and closed. Their breath is loud or stops or moves in a sudden whoosh instead of a soft, steady stream. They seem to be pushing or holding on fiercely.
I see too much sukha when a student's spine looks collapsed. When their bodies surrender and suddenly look too heavy for them to hold. Their breath is uneven or too faint or quick. They are disengaged, and their attention flits from one thing in the room to another.
When my students achieve sthira-sukha in class, I can see their eyes and faces are calm. Their bodies have a sense of endless inner strength. They are fully invested in the practice, and move and breathe with a purposefulness that brings the work to a deeper level than just their bodies.
Until they have sthira-sukha, they are doing exercise. Yes, it might be useful exercise. But when they have the balance of stability and ease, they are doing yoga.
If you've ever been in the room during one of my classes, I'm sure you have felt the difference.
When people are really doing yoga, they have presence and a deep power about them. They aren't just going through a series of motions, or following instructions to get somewhere. They are completely engaged, and they get more benefit from the practice as a result.
What they are learning through their bodies becomes a part of them.
It takes repeated practicing over a period of time to know what sthira-sukha feels like, and to be able to find it again. That's why I encourage students to practice, every day. It doesn't have to be a full 60-minute sequence to be incredibly useful. Five or ten minutes is enough to remember how to be stable and easy in your body. And eventually, that feeling becomes the norm.
When it does, then you are no longer distressed (an-abhighātaḥ) by conflict (dvaṅdva).
When you have mastered this feeling of sthira-sukha, you know it so well that things which caused stress before no longer bother you.
You know you are capable of meeting challenges directly, without strain or avoidance.
You no longer worry about what will happen, because you feel safe, strong and easy inside.
The feeling of steadiness and ease has become a part of who you are.