
I was really at the end of my rope physically, mentally, psychologically, quick to get aggressive.
With every session I noticed that I’m mentally fitter, my head is clearer, I can make decisions faster.
Stabiler Kern
Head full? Hard to switch off?
Live with me, online or in person.
“If I hadn’t had that breathing session with him, I probably wouldn’t have coped at all mentally.”
Andreas, department head at a large company, father of two, building his own business. · Translated from German · video in German
Exhaustion rarely comes from too much work. It comes from missing boundaries.
The training
60 minutes, live with me.
60 minutes, live with me.
60 minutes, live with me.
In these, you learn the matching tools.
Online or in person.
The direct result of your tools isn’t coming down. It’s that this much load doesn’t build up in the first place.

3 × 60 min
Breathing System Reset, Nervous System Reset, Nervous System Load Training.
3 × 60 min
In these, you learn the matching tools.
4 weeks
Live and 1:1, online or in person.
About me
Sergius Geier is the founder of Stabiler Kern. He works with men who function on the outside but whose heads won’t switch off anymore. He is a master of Korean martial arts and works with breath, movement and bodywork.
In 2020 he hits his own limit, exactly the man he warns about today. Instead of giving up, he fights his way back. Step by step he rebuilds himself, physically, mentally, emotionally, and returns to martial arts, all the way to master rank.
“I did have tools and options, but I was missing the framework and the basic structure.”
How solid this work is becomes clear between 2023 and 2025, when everything comes at once: his company is on the verge of closing, and at the same time he is hit by severe strain in the family. More pressure than ever before. But this time, what he has built up over decades holds.
Client voices

I was really at the end of my rope physically, mentally, psychologically, quick to get aggressive.
With every session I noticed that I’m mentally fitter, my head is clearer, I can make decisions faster.

All that stress got me to the point where at every little thing […] I’d go off like a rocket straight away.
After the first session, I’d say I’m a completely different person.

Something in my body told me, okay, now it’s too much.
I’ve got better energy. Like, for example, today was the first time I actually slept well.

Everything just came at once. One piece of bad news after another.
But at the end of the session I immediately felt how relieved I was.
“[…] I also couldn’t find any time for myself to come down and switch off. […] at the end of the session I immediately felt how relieved I was.”
“[…] I don’t know when I last felt this light. Feels like a whole lot of weight has come off my body.”
Now that a bit of time has passed since the session, honestly - I don’t know when I last felt this light. Feels like a whole lot of weight has come off my body. I just feel good, but a really fulfilled, content kind of good.
Even if I still can’t really put into words what happened there, even though I’d really like to be able to describe it to myself, the result so far speaks for itself. I was in a state that just flowed - no real thought, no words - and yet just right.
Thank you so much from the bottom of my heart for the opportunity and your support/ guidance. You really radiate that 1000%, and I felt super safe the whole time! Thank you for that 🙏
“[…] my head is clearer, I can make decisions faster. I don’t let negative stuff drag me down so badly anymore.”
“My personal goal was to come down from everyday stress […]. On the drive back I was already solving problem cases with new energy.”
Bro I’m the one who should be saying thanks 😘
I deliberately didn’t read up on it beforehand, because I trust you. When I saw the health questions and the preparation, I did get a bit of a nervous feeling. I’d pictured it as a kind of more professional yoga class. My personal goal was to come down from everyday stress and to learn a technique for it. But after the session that was just a side note and turned out to be an interim goal, which was fully reached. What I got was indescribable. Detached from all thoughts and from my body, there was nothing to feel. Afterwards, noticeably full concentration, a mental reset and no negative thoughts. On the drive back I was already solving problem cases with new energy. Looking forward to the next session. Thanks a lot!!
“Something in my body told me, okay, now it’s too much. […] I’ve got better energy. Like, for example, today was the first time I actually slept well.”
“[…] it’s like a huge weight fell off me. […] the next day I somehow felt a lot lighter.”
“The next day I had a situation where I normally would have hit the roof straight away. But I was calmer and more relaxed in that situation […]”
That was my first breathwork session, thank you so much for your time and the opportunity!
I couldn’t really picture what it would be like, so I was a bit nervous.You did a really great job, your calm caught me right away and the nerves were gone.
The session was very interesting and emotional, with your help I can close the chapter on a very emotional issue for me and look ahead.
After the session I was tired but also very relaxed and calm.The next day I had a situation where I normally would have hit the roof straight away.
But I was calmer and more relaxed in that situation, I’m really curious whether it’ll get even better with the next sessions.I’ll definitely take the chance to do more sessions.
“With every session I notice how I can let go more and more. […] I wasn’t aware before how many old tensions, fears and emotions I’m still carrying inside me […]”
I’m still speechless about my third breathwork session – it was an absolutely breathtaking experience, and I hadn’t expected it to go this deep. With every session I notice how I can let go more and more. In this third session I was able to dive into deep-seated blockages and process so much that I didn’t even know was inside me.
I wasn’t aware before how many old tensions, fears and emotions I’m still carrying inside me – some of them go all the way back to my childhood, others are about current issues. Feeling and living through such a long span of time was intense, but at the same time incredibly freeing. I was even able to forgive certain people from the bottom of my heart and release physical as well as emotional tension.
This experience showed me once again how powerful breathwork is – and I’m sure it wasn’t my last session. Thank you for this safe space and the caring guidance along this path. So much healing is possible – and I’m endlessly grateful for it.
“Thoughts, feelings, memories – things that usually stay in the background became visible.”
The second session went even deeper – not in the sense that more “happened”, but in that I felt myself on a whole new level. I don’t see myself as a particularly emotional person, but in that space something could surface in me that normally finds no expression. Thoughts, feelings, memories – things that usually stay in the background became visible. It was as if someone had held up a mirror to me that shows what otherwise stays hidden.
“Before, I had a stress-related tic that had been with me for quite a long time. Without any conscious work on it, it was simply gone after the session.”
I went into my first breathwork session without big expectations – just open to whatever might happen. What came then touched me on a deeper level than I could have imagined. It was as if someone had opened up access to a part of me that I had never consciously entered myself. Two emotional waves came up, completely unexpected – and yet they felt right. As if something was starting to move that had been waiting for a long time.
What impressed me most was the effect that showed after the session: Before, I had a stress-related tic that had been with me for quite a long time. Without any conscious work on it, it was simply gone after the session. That made it clear to me how deeply this tool can work on a physical and emotional level.
Do you recognise yourself?
Are you at the end of your rope physically, mentally and psychologically, and quick to get aggressive?
Have you taken a lot onto your shoulders and don’t really know what to tackle next?
Do you bottle everything up, your fears and your worries?
Does all the stress make you grumble at every little thing or go off like a rocket straight away?
Is everything coming at once? One piece of bad news after another?
Do you wake up already irritated because you still have so much to get done, plus tasks left over from the day before?
Do you not know whether you can switch off, because you’ve got nothing but problems on your mind and still plenty to get done, for work, in your private life and so on?
Is something in your body telling you: okay, now it’s too much?
At a glance
Price
On request
Common questions
Intro call
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