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My name is Mitchell Slier
I am a Coach and Fighter at Mejiro Gym Bali.

Book a private training session with me or send me a message if you have a specific question for me that you can't find in our FAQ
Mejiro Bali Coach Mitchell
A little bit about Mitchell
Nickname : Coach, Sensei, Mitch
Fluent in : Dutch, English, Indonesian
I was a hothead and an active boy who was very into sports since a young age. In the beginning, to prepare me for self defence, my dad signed me up to Kyokushin Karate at the age of 5. At that age, I mostly dreamt of becoming a professional football player.

I had already earned my green belt in Karate when I was forced to move to another dojo because the dojo I was training in was closing permanently. I had to restart from white belt in the new dojo. I really disliked it because it took me many years to get to green belt but because of this change, I began to understand patience and the power of not giving up. In the meantime around the age of 11, I also started to do Kickboxing in my father’s gym. I eventually left Kyokushin Karate to train fully on Kickboxing.
Focusing on Dutch-Kickboxing
Fast forward to the age of 15, I was seriously injured in a football training, being sidelined, I felt like I wasn’t part of the team anymore, it was a heart breaking time. It made me realise that team sports wasn't for me, so I made a big decision to let go of my childhood dream of becoming a professional football player and really put all my time into Kickboxing. After truly focusing on this particular combat sport, I finally recognised that it was good for me and my self control. The decision felt right, I started to fall in love with the sport as it also improved my physique.

At the time Mejiro Gym was going to be opened in Bali. During its construction I learned a lot from a Mejiro Gym veteran Sensei Frans Visser. He opened my eyes on what Dutch Style kickboxing is all about, how it is both an elegant and effective fight style. A year later sensei Andre Mannaart and K1 champion Roel Mannaart came to Bali, where I joined his seminar and discovered many drills and technique combinations. Being coached by them directly had inspired me to train harder.
The team of Battle of Bali, Coach Mitchell in the Middle
Fighter for Team Mejiro Bali
On the 1st of September 2020, Mejiro Gym Bali officially opened to the public. I was entrusted the responsibility to instruct classes at Mejiro Bali, which I gladly accepted because through this opportunity, I was able to share my passion for the sport with like-minded people and learn to improve myself everyday in the process. Learning Kickboxing is training me of the real meaning of discipline, hard work and applying in real life the 'not giving up' mentality to survive and keep on pushing forward.

On the 27th of  November 2021, I had my debut fight match, I was 17 years old and my opponent was 24 years old with a record of 12 fights 9 wins 2 losses. I felt confident with my skills and mental control so the difference in experience and age only encouraged me more. Despite that, I felt anxious before the fight but it all went away when I stepped out of the locker room. The fight was in pro rules (no headguard, no shin guard). I won’t spoil what happened, if you're curious, visit a record of the match on YouTube.

Come to the gym and train together with me or stay tuned for more of my fights for Team Mejiro Bali!
A Sneak Peek of my Mejiro Bali Team


Questions-and-Answers with coach Mitchell

In Bali, what other activities can I do to improve my performance outside the gym and enjoy Bali at the same time?

You can swim in many beautiful beaches in Bali, I like to visit Jimbaran beaches, Uluwatu & Nusa Dua. Swimming in the waterpark, Bali waterbom for some thrill seeking and sun is also nice.

Do you have a favourite food in Bali, to take before training or unwind after training?

My go to food after training is either Tuna Steak or Italian food in forketta Sanur, especially their tiramisu for cheat day dessert.

Can I specifically book a private session with you? 

Yes you can request a private session with me, simply book a session and write in the details which coach you would like to train with, but keep in mind that the coach might not be available at the time / day that you requested and your booking will be rescheduled.

Having been raised into Kickboxing in a Boxing gym, do you still get nervous in the ring?

No, I rarely get nervous rather it feels like home. If it is your first time in the ring you should try being comfortable at first and make the ring your playground, maneuvering the ring comes with time and practice. Don’t fear the ropes or worry about being cornered, only regular sparring practice can ease your worry.

Do you have a fighter that you admire and inspire the most?

Yes infact I take a few styles from each fighter that inspires me to make my own style. Boxers that I look up to the most; Mike Tyson aggressiveness (his killing aura / mindset), Gervonta Davis (timing power), Floyd Mayweather's tight defence, Canelo's signature head movements, the style of 'The Diamond' Ramon Dekkers for Muay Thai, aggressive combos from Ghokan Saki, lowkicks from Rob Kaman and Ernesto Hoost.

With all the regular sparring and extensive training, what was your worst accidents / injuries?

Nothing too bad just the occasional black eye bruising from not defending properly, quite often from a kick to the balls (to all the men, wear groin guard) and I hurt my wrist once because I didn’t make a good fist.

Come for a

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