It's not so important that you are a good kicker yourself if you have enough other strengths, but it's important to know kicks so you can defend them.
Kicks can be very devestating. A clean head kick for example often equals a KO, low kicks can slow or even knock the opponent down, front kicks can help to keep the distance, kicks to the liver can result in knock downs (people who get knocked down by a liver shot often wish it would be a KO, because it's tremendously painful). But of course kicks have the disadvantage of giving up your balance and making you vulnerable to take downs.
Heck yeah they are important. I struggle with them sometimes because Im tall for my weight class so I don't want to risk being taken down at that point. But when I do kick its an inside leg kick. It will either hurt them or make them check it which sets up my single leg.
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Its almost as if I like to be tapped out! lol
As someone who used to be a big kicker, who's coming off of a 4-month stint where I trained nothing but my hands, my opinion is a resounding 'HELL YES!'
As others have mentioned, kicks are very damaging, have longer reach than punches, and give your attack a little bit more variety. Even more important than those very worthy examples of the importance of kicks is the fact that their inclusion changes the range of the fight. Without kicks, the neutral ground/no man's land is just beyond jabbing range. That is where you are safe to feint and play with the distance, and it is from there that your attack will be mounted.
When kicks are in play, however, the outskirts of jabbing range is no longer a safe zone. Coming back from a stint of boxing-exclusive training, that was really tough to cope with. I'd habitually look for that range to play in, but that was to my detriment for two reasons...
First, whenever I'd settle there, I was within my opponent's reach in terms of kicks. Action is faster than reaction, so having space between you and your opponent can give you that extra milisecond you need to react. When I would sit contently within kicking range, I was constantly getting pelted in the legs while I was trying to find my range with a jab.
Second, because my opponent is wary of kicks (even though I wasn't throwing them often), he would look to establish himself at the edge of kicking range. So whenever I would try to set up camp at the edge of jabbing distance, he would already be on his bike -- rightfully perceiving my narrowing of the distance between us as a threat.
TLDR: He would never let me settle into the range I needed to get off punches/I would chill within perfect reach of his kicks, hence be a sitting duck. Kicking changes the range of the game, and if you don't kick, you're much more limited not only in the angles and heights of your assault, but also in your distancing. Furthermore, you automatically concede the kicking range to your opponent, making it that much easier for him to control the fight.
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Highly opinionated but out of touch with the current MMA scene.
Yeah I can defend against them ok, I just suck at throwing them any higher than the leg, I just can't seem to get any power into higher ones, and I guess I'm probably at risk at getting them caught and being taken down. I guess it's a good idea to keep learning them but I noticed that there are a higher percentage of KOs in mma from punches than there are from kicks, knees and elbows, so not that worried about it also I'm quite a short guy so would be fighting taller people, don't think it would make sense to be trying to throw high kicks.
This might make you feel better.
Im tall in my weight class. And I never try higher than the legs and maybe, if im feeling brave, the mid section.
My legs are rather in-flexible. I can generate power but dont feel confident in my kicks.
But I just know thats one of the many things I need to work on.
So in better words, yes they are important so practice them.
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Its almost as if I like to be tapped out! lol
Yeah I can defend against them ok, I just suck at throwing them any higher than the leg, I just can't seem to get any power into higher ones, and I guess I'm probably at risk at getting them caught and being taken down. I guess it's a good idea to keep learning them but I noticed that there are a higher percentage of KOs in mma from punches than there are from kicks, knees and elbows, so not that worried about it also I'm quite a short guy so would be fighting taller people, don't think it would make sense to be trying to throw high kicks.
Bas Rutten can help you out with getting power into your kicks. It's not quite as fast and non-telegraphed as the traditional way of throwing kicks where you pivot off the lead foot, but it's got a heck of a lot more power behind it.
Kicks are extremely useful. They help a lot with distancing and opening up your opponent. You can mix em up well too. Doing an uppercut to hook, seperate, throwing a leg kick to jab, seperate, hook hook leg kick, or body kick or whatever. It keeps your opponent guessing.
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Sweet sig by Life B EZ
I feel like I get paid way to much money, but not enough -Nick Diaz
It is important. It is an extra tool in a mma fighters arsenal. I agree with the danger of kicks and a counter takedown, but there are other less committed kicks with less chance of take downs such as inside low kicks which imo gsp does very well, its almost a jab... as well as dan henderson's inside leg kick set up for the big right hand.