i think there's a lot of confusion because both are presented as "real-world, dirty" defense arts. And that is certainly true, but in systema's case vastly oversimplified
Krav is a collection of effective yet not technical moves. Everything is kept simple and based on gross motor activity to make it accessible during an adrenaline dump. Krav's formula is this: block incoming attack while already attacking, and continue attacking in a barrage of painful ways until the attacker is down.
It took me awhile to understand what systema is, and you kinda have to go to a session to really get it but here goes.
Systema is an art based not at ALL on technique but entirely on principles. The principles are:
-relaxation
-breathing
-understanding human motion and balance
-knowing where to hit, push, or pull people to affect their motion and balance
-how to receive opponent's energy and transmit muscle tension into effective strikes
-knowing how to take strikes, pushes, without losing balance or succumbing to pain
All a systema training session is is a serious of drills designed to assist the the student in understanding those principles both mentally and also their body motion memory. Techniques are demonstrated not to be copied but to give students ideas of possible movements.
The goal is to practice reacting to attacks so many times that the process occurs automatically, kind of like "flow"
I wouldn't believe this if I didn't get my ass handed to me in extremely creative ways by a systema instructor. YOu try something and then you're on the ground, and you don't know how you got there. Except he's still standing and has you in an armbar.
It takes dedication but you can pick it up quickly with the right progression of drills and patience. I've sparred with people who'd only done it a year, they're very fluid and effective. Those who've done it 3+ years seem almost untouchable and can do smooth multi-opponent work. To answer your question, a 5-year systema practitioner would take out each other guy probably within seconds.
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