Advanced yoga poses don't necessarily have to be more difficult. You can make a yoga pose more advanced simply by the awareness and understanding you apply to doing that yoga pose.
As an example, a beginners version of upwards bow would include lots of modifications and preparation poses so that the student has the opportunity to learn to feel their body and undernstand what they are trying to do. They can then focus on working towards the pose. However, an advanced person can focus on little details without the warming up. Instead they can move into a pose step by step, or all at once, while focusing on different parts of their body as they do actions specific for each of those parts.
The funny thing (or the neat thing) is that the better you understand your body and how it works, the easier it is to work towards poses that require a high level of flexibility, strength and body awareness.
With advanced poses, if you are good at breaking things down, figuring out how to problem solve, and if you can sense your body and control it reasonably well, then you can make advanced poses easier, or at least work towards them intelligently. And if you aren't, then I hope that this article can help you acquire the neccessary smartness.
One pose that could be considered advanced is urdhva dhanurasana. I used to hate this pose especially at the end of an ashtanga practice when my mat was soaked with sweat. I was always worried about my hands slipping. Even without a slippery sweat soaked mat, upward facing bow pose can still be challenging, especially if your focus is on using your arms to lift the weight of your body. Using your arms is difficult in this pose because they can be close to the limits of their range of motion. And so one way to get around this is to practice using your legs.
Another posture that may fall under the advanced yoga pose heading is the front to back splits or hanumanasana. This pose can be difficult to improve because because in order to stretch the muscles of your legs you need them to relax however, at the same time you are using your legs to support your body and this requires them to be strong. One way of getting around this is to place your hands on blocks or chairs so that you can use your arms as your foundation. You can then focus on reaching your legs front and back. Then, once your pelvis touches the floor you can relax.
Another approach is to rhythmically squeeze and then release your legs, gradually working deeper into the pose by slowly contracting your legs and then slowly releasing them, each time you release, allowing yourself to go deeper while maintaining control.
Side splits, or equal splits is the same deal. You are trying to stretch your inner thighs but at the same time they may be tensing to support the weight of your body. What do you do? One alternative is to do a half side split. Bend one knee and rest it on the floor. You can rest your elbows on the floor and as you sink deeper you can then rest your chest on the floor. If your hands are in push up position you can slowly lift your chest and lower it to add weight to the pose. (You can then use this weight to gradually stretch your inner thighs.) Once you start getting deeper while doing half splits you can then try to do side splits with both legs straight. Here again you can, as in the front to back splits, work at squeezing your inner thighs and then releasing them.
In both cases, work at gradually contracting and gradually relaxing the muscles that you are trying to stretch.
A pose like dancer is difficult because it requires extreme shoulder flexibility to get into. Plus hip flexibility. Is there a way to work into it and poses like king pigeon if your flexibility is limited?
I'll own up here to the fact that I don't practice this pose and I can't yet do it (because I don't practice it.) however, with some awareness of your shoulder, you can learn to position your shoulder so that you can work towards getting into the pose. And as with the splits, when reaching your thigh back you can practice tensing and squeezing the muscles you are stretching so that you can get your leg deeper into the pose as well.
And what of foot behind the head?
Marichyasana d can also be difficult and labeled as an advanced yoga pose because you have a very small foundation, one leg is in lotus and you are trying to twist at the same time. I first learned about this pose while doing ashtanga yoga but rarely if ever can get into it. the days that I do get into it I use one of several Marichyasana d preparation sequences. Rather than heating my body up to get into the pose I focus on relaxing it and being away of how the parts of my body relate. It can be as simple as moving the hip of my lotus knee forwards that helps me to get into the pose. However, that isn't the only thing and so part of any advanced yoga pose is learning to juggle or balance different actions so that you can reach the final pose (or your variation of it.I)
Handstand, headstand, and forearm stand may also be declared "advanced" since they require elements of balance while your body is upside down. Part of the trick with dealing with these poses is getting used to being upside down. Another element is learning new references to make controlling your body (and teaching) easier. To other important aspects are learning to use your shoulders and your waist. Rather than exercising your abs, here is a chance to learn how to use them.
For some of you the poses I've listed as "advanced" may not be all that advanced. It all depends on your experience, understanding and ability. In all cases what is important is that you have a clear idea of what you are trying to do in each pose. If you have that clear idea you can figure out ways to work towards a yoga pose whether it is advanced or basic. What if you don't know what you are trying to do? Then try the pose anyway and use that "experiment" to help you understand what you are trying to do. Or at the very least figure out what limits you so that you can then work at pushing back that limit.
In all cases, where possible, see if you can figure out how to move into a posture smoothly and slowly and with control and awareness. If you can't do that then break down the pose into elements so that you can do those elements smoothly and with control.
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