Sati1 wrote:1) Turning head: has anybody experienced their head turning to one side during meditation, or leaning back? In almost every session, my head begins to turn left, and sometimes it leans back. Sometimes I would leave it there, and sometimes I align it straight again.
This can be an opportunity for mindfulness. This seems to suggest a lapse in awareness of the head and neck orientation during the motion itself. Can you catch it when it first starts to happen, and just hold still? Can you catch the change in intention regarding the head and neck muscles before it happens, and just hold still?
Sati1 wrote:2) Open eyes and nimitta: when I first started to meditate about a year ago, my eyes would be closed for the whole session. Then at some point they started opening, and now they are open half-way from the beginning into the whole session every session. I have tried to force them closed, but the strain becomes a substantial distraction. Since I consistently enter access meditation without entering the first jhana, I wonder if that's because the open eyes prevent arising of the nimitta (which I haven't really experienced yet).
Some teachers recommend open eyes, some recommend closed eyes. Closed eyes can cause more drowsiness, while open eyes make it easier to stay awake but can tempt the attention to the visual field. If you decide to go with open eyes, perhaps set up your sitting position so that you're facing a blank wall. This way the distraction is minimized. If you decide to go with closed eyes and it feels forced or tense, try to find the source of the tension and relax it. This can be done with normal body scanning and relaxation approaches around the eyes themselves. If you start to get a headache while doing scanning in the head area, however, this might not be a good approach.
Sati1 wrote:3) Chair: Due to a weak and inflexible back. I have struggled to meditate without back support, and currently only meditate while sitting on a chair. Would you recommend training the back for strength and flexibility to enable sitting without back support, or is meditation on a chair "good enough" for life? I am 32 years old and am looking to develop a posture that can last a lifetime.
If there's no underlying health issue, it might be worth investing a few minutes before each sitting session to do some back strengthening and stretching exercises. If you have the opportunity to receive yoga instruction regarding such exercises, they can be quite beneficial for your long term health. If there's a fundamental health reason why your back is unable to sit without a chair, then a chair can suffice. If sitting in a chair is difficult, you can practice standing, walking, or lying down as well. Sitting is often preferred because walking can be too active to really get the mind to settle down, standing can become tiring, and lying down can cause drowsiness. The practice is ultimately something you do with your mind, though, so whatever position works best given your physical health is still better than nothing.