The 2 are quite different. Today we will look at breathing for kundalini.
For kundalini, chakras, tattwas (elements), koshas (body sheaths), pranas, what is most helpful is to do pranayama which creates an energy. For it is energy, along with consistency, that gets things moving. So, in this instance, we are focusing on moving our bodies via dynamic asana (postures), stimulating & moving our prana (life-force), especially the seat of prana, which is around the navel region. We are creating an internal heat which also aids the revealing of the inner realms. Everything is about movement, & even when we move into a more peaceful pranayama to conclude our deep breathing session, we are restoring a balance, between both brain hemispheres, we are creating a mental & emotional equilibrium, we are allowing the pranas & nadis (subtle energy flows) to calm into an auspicious state, for meditation. In meditation, for all of the spiritual aspects mentioned, it is still about energy, movement. An energy moving technique that keeps the internal aspects flowing, aids in allowing the countless accumulated mental & emotional impressions, to flow, in meditation. Before we have finished, the movement of energy, then balance, followed by meditation, leaves our entire complex in a sublime state. If you are not calm after all this......your practices need refining or changing. I have seen, over the decades, so many aspirants lose heart with their practices, as there is too much revving up without this calming, restoring ending to one's practices. And constant revving up without calming after, creates an agitated mind.
Always finish your asanas with 1 or more calming, relaxing, internalising poses. Reclining butterfly; reclining spinal twist...both are excellent, especially if held for a minimum of 5 long, relaxed breaths, each. I personally end with this, nearly every morning. Seated cross-legged twists, followed by forward bend, still cross-legged, are a good alternative.
Then start pranayama. Bhastrika, emphasing a forward/inhale & backward/exhale, pumping action, at the navel region, is the number 1 pranayama for energy. Do about 1 - 2 bhastrikas per second. Work up to 120 bhastrikas each day, in 1 sitting. When you can do this, add a chin lock & root lock, on the inhale, at the end. You can do bhastrikas differently than this, however for energy: it's all about pumping that navel, creating energy, heat.
If you have high blood pressure, heart problems, anger issues, then bhastrika, big breath retentions, & locks, are an absolute NO!
Another caution: bhastrika done this way stokes the internal fire, so it is very powerful. I personally have had long periods of doing much more bhastrika at 1 sitting, but....& this is important....this requires guidance, & the correct situation to be able to do this.
To finish with bhastrika without calming our system after, is counterproductive. Everything in life is a balance, & even in spiritual technique, this balance is essential for our whole being.
Follow with nadi shodana, for balance & calming: in/left nostril; out/right nostril; in/right; out/left; to equal 1 round. Start with relaxed uniform breathing (inhale & exhale being roughly equal), & work up to 5 rounds. When you can do this, add the exhales being 2x as long as the inhale. Then you can add ratios. An achievable ratio to start with is in 3; out 6. Then it's in/3; hold in/6/internal retention; out/6. When this is achievable, add external retention: in/3; hold in/6; out/6; hold out/3/external retention. The next level is 4:8:8:4. Then 5:10:10:5. For longer retentions, we are looking at adding locks/bandhas.
Meditation comes next, however today it's more about the pranayama for energy, so I shall end here. When we look at pranayama for stress reduction, you will see that the 2 approaches & techniques are quite different.