It comes from Israel, has thousands of devoted followers and is popular with celebrities.
But what exactly is krav maga, and how does it work?
To find out, I sought the help of Joel Bennett, an instructor at the Zut Krav Maga centre in Hendon, north-west London.
He agreed to show me the basics of the unarmed combat technique in a one-hour session this week.
But, before we could begin, he had a point to make. Simply disarming an attacker and then fleeing, as MPs are reportedly being trained to do, was "not possible".
KM - What you need to know
● Krav Maga is a self-defence system developed for the Israel Defence Forces.
● It was created by Hungarian Imi Lichtenfeld to protect Jews from attack in pre-war Bratislava.
● Celebrity followers include Tom Cruise and Daniel Craig.
● It combines boxing, wrestling and judo. Students are taught to target the most vulnerable parts of the body.
His advice was to run away, and if that wasn't an option, to fight back with as much force a possible.
"No one wants to think of themselves as violent or capable of being so. But if you can't run and your only option is to stay and face the attacker, I want you to be able to defend yourself and that is impossible without making contact."
In his studio, surrounded by mirrors, and punch-bags, he showed me four moves that could help me protect myself.
The first instruction was to adopt a defensive position with my hands up. At the same, he urged me to shout out at my "attacker": "Don't come any closer, stay away".
"If your stance and voice are confident and you don't look like a victim, that could be the difference between him picking on you or someone else."
Aggression could keep me alive, he added. "You need to change from a placid person who wouldn't hurt anyone, into someone confident enough to cause enough damage to the person."
Anything could be used as a weapon or a barrier - a handbag or rucksack, for example.
He made me hit out at a punch-bag while shouting. My voice echoed in his quiet studio.
Next, he showed me a simple groin-kick. And if my attacker managed to get hold of me, I could attempt to loosen his grip by gouging his eyes.
Explaining how to punch effectively, Mr Bennett instructed: "Clench your fists and punch downwards to hit the nose, or if they've grabbed you and you can't hit the face, hit the back of the neck. You need to hit hard and with aggression."
The instructor , who has two decades' worth of experience, warned that years of training was necessary to be able to disarm an attacker, and even then "the recommendation would still be to run".
Putting it bluntly, he told me that if someone with a knife has the intention of killing me, the likelihood is that I will get stabbed.
And, because of this, we ended our session with first-aid training.
He said: "You might do enough damage to run away but the chances are high that you'll be cut in the process.
"If you are cut in a main artery or vein you'll have two minutes until you bleed to death."
He demonstrated how to stem the blood by using a tourniquet, buying a victim up to nine hours in which to receive medical attention.
He said: "In the Bataclan attack in Paris, it took police hours before they could get in there and help people.
"Do you want to risk your chances waiting for them or learn something simple that could increase your chance to survive?"
Zut Krav Maga centre on 07976 756396. www.zutkravmaga.co.uk
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