I do not know what kinds of hand to hand (H2H) combat are standard systems in the Units similar to GROM. In my opinion the GROM system, however, is interesting enough for sharing here some information about it – namely the GROM Combat, created IN and FOR this Polish SO Unit.
What is the GROM Combat? This system was created as an answer for a problem that was noticed, among others, by Leszek Drewniak (an officer responsible for H2H combat training in the new established GROM). In the new Unit there were many of H2H combat specialists-box, jujitsu, krav-maga, judo. The result was a kind of mix, which elements were easy to adopt for some men and at the same time they were difficult for the others.
The creators of the new system (Jacek Kowalik was working on the system together with Leszek Drewniak) focused on a very individual training.
First, they monitored each of trainees, paying special attention to his physical aptitudes, abilities, and skills. Then the suitable set of techniques was chosen for each men-from a few to dozen or so.