Garudasana (Eagle Pose)

Garudasana, Eagle Pose, is a standing balance in which one thigh crosses over the other, one arm crosses over the other, and the whole body sits down a little on the standing leg while wrapping itself up. Garuda is the eagle of the Indian tradition, the mount of Vishnu, so the name refers to a specific figure rather than to birds in general.

It is two poses in one, and they can be separated. The legs are a balance and an outer hip pose. The arms are an upper back and shoulder stretch that reaches the area between the shoulder blades, which almost nothing else in a standard practice touches. The arms can be done sitting on a chair, at a desk, in twenty seconds, and I would rather a student did that four times a day than the full pose once a week.

It is not a pose about hooking the foot behind the calf. Whether that happens depends on the length of your shin and the proportions of your legs as much as on any flexibility, and plenty of people will never manage it. Leaving the toes of the crossed foot on the floor gives the same balance training, the same leg work and much less twist through the knee.

Where it belongs is in the balance group, after the standing poses have warmed the legs and before the floor work. It goes alongside Vrikshasana, which is the simpler balance to learn first, and Natarajasana, which is considerably harder. It should not follow Utkatasana immediately, because a thigh that has just been worked to trembling makes a poor balance leg.

Balance is a skill and it is trained by holding steady positions, not by falling out of unsteady ones. That single idea changes how this pose should be practised.

• Use a wall. One hand, one fingertip, or simply standing near enough to touch one. The wall lets you hold the shape for eight breaths, which is where the training happens, instead of spending the hold catching yourself.
• Bend the standing knee. A locked leg is a stilt. A bent knee lowers your centre of gravity, engages the thigh, and makes the small corrections at the ankle possible.
• Fix the eyes. One still point, about two metres in front of you, on the floor or the wall. Not the ceiling fan. Not another student.
• Spread the toes. A foot that grips the floor with curled toes is a foot in trouble. Weight on the four corners, toes long, and the ankle can do its job.

There is a good reason to bother with all this. In a twelve week programme of standing poses for thirteen older adults, postural control improved measurably on the Mini-BESTest, the timed up and go improved, and fast walking speed improved by more than the threshold considered clinically significant for that age group. It is a small study and the direction is clear: standing balance responds to practice. That is why balance poses are the part of a practice I am least willing to let anybody skip, and why holding a wall in order to keep them is entirely sensible. The case for keeping this kind of work is set out on yoga for beginners over 40.

One caution from the same body of biomechanical research: single leg standing poses load the ankle joint noticeably, and people with ankle degeneration should be careful. Keeping the crossed foot's toes on the floor spreads the load over two feet and answers most of that.

Cross the arms above the elbows, bend both elbows so the forearms come upright, and bring the palms or the backs of the hands towards each other. Then lift the elbows slightly and draw the shoulder blades apart. That last instruction is the pose: the stretch should spread across the upper back between the shoulder blades, which is exactly where a person who works at a screen aches by four in the afternoon.

If the arms will not cross, hug yourself: each hand to the opposite shoulder, elbows stacked. This is the same stretch and it is what I use with anybody who has a shoulder history. What should never happen is the shoulders climbing up towards the ears, which turns an upper back stretch into a neck complaint. The rule is the one that runs throughout yoga for neck and shoulder pain: no arm position is worth a neck.

The reason to know this half of the pose separately is that it is portable. Twenty seconds, sitting, no mat, no floor, no change of clothes, twice in a morning and twice in an afternoon. It is one of the two or three genuinely useful things in the desk sequence, alongside a chair twist, and it is the recommendation I make most often to office workers who tell me they have no time to practise.

Do both sides. The arm that goes on top the second time will feel entirely different, and the difference is information rather than a problem.

Balance poses are held for a moderate time and repeated, and the aim is a steady hold rather than a long one.

Every day is fine, and the arms can be done several times a day. Balance responds to frequency more than to duration, so twenty seconds a side every morning beats two minutes a side once a week, which is the same argument as in how often should you do yoga.

In the balance group, after the standing poses and before the floor. A workable order is Tadasana, a few rounds of Surya Namaskar, the warriors, then Vrikshasana, then Garudasana. Learn the tree first: it is the simpler balance and it teaches the standing foot.

What comes after is standing still. Tadasana for one full breath, weight even on both feet, is the counter pose, and it also lets you notice how differently the two sides feel. Then a forward fold, and then the floor.

Do not put this pose straight after Utkatasana or a long Warrior hold. A thigh that is trembling is not a balance leg, and all you will train is frustration. Leave a fold or a standing pause in between.

The arms have a life of their own outside a practice. Twenty seconds at a desk, twice a morning, is worth more to a screen worker than an ambitious weekend class, and if you want to know where else that logic applies, how often should you do yoga makes the case for small and frequent over large and rare.

Balance poses are the group most often skipped and they are the group most worth keeping, so the modifications matter.

• Vertigo or an inner ear problem. Arms only, sitting. Do not attempt single leg standing until somebody has looked into the dizziness.
• Ankles. Keep the crossed foot's toes on the floor and hold a wall. Single leg standing loads the ankle, and an ankle with degeneration or a recent injury should not carry the whole body while wrapped up.
• Knees. Cross the thigh lightly, never at the knee, and keep the toes down. After a knee replacement, practise the arms only.
• Shoulders. Hug the opposite shoulders rather than crossing the forearms, and never let the shoulders lift towards the ears.
• Blood pressure and faintness. Short hold, eyes open, wall within reach. See yoga for high blood pressure for the general approach.
• Pregnancy and hip surgery. Arms only, seated, for the first, and a conversation with your surgeon for the second.

Almost everybody can do a version of this pose, and almost nobody should do it in the middle of an empty room in their first month. If you want somebody to set your version, come to a class and be watched, or start with a first class.