When looking for self defense classes or a private instructor, you must look for experience. Some people may say they are certified in self defense, but there isn't actually any accrediting association for certification in self defense. If they have something that's says they are certified in self defense, it is just something they paid for from a website to look official. Choose an instructor with no less than three years of martial arts (or related) experience. Check references. If possible, speak to your potential instructor's teacher. Their teacher, especially from arts martial arts background (they teach a lot of honor and respect), should give you the truth on your potential instructor's abilities.
A lot of people get confused with which type of discipline to choose for self defense. There is kickboxing, boxing, karate, taekwondo, akido and krav maga and many other forms that can be used for self defense. Some people may say that taekwondo is for tournament fighting and not practical, but whoever has a discipline compared to those who don't increase their chance of survival in an attack. The truth is, they are all good, just use the one that you like the most.
Bad guys are bad because they like to harass, torment, hurt people and steal. They are too lazy to to contribute to society. If you get attacked by someone and you have a discipline, you have a great chance of having the victory. Chances of a bad guy knowing any real fighting techniques are very little. All martial arts and self defense disciplines teach fighting as a last resort (outside of tournament competition) and only for self defense or for defending someone else. Because the this type of integrity is imbedded into the student's mind, it is unlikely that your attacker has any formal knowledge on fighting. The attacker's only skill comes from attacking people without a discipline or from getting into fights with other bad guys who do not have any skills.
Man, woman, young or old, should all learn self defense. A person can start learning these type of disciplines at a very young age. And older people can learn these things as well. Even if a person is not in super athletic shape, a lot of these skills are pressure points of the body, joint locks or striking points that most people can learn and use. No need to learn how to do a jumping spin kick when a front kick to the attacker's knee will do.
How much taking classes costs will be a lot of people's concern. This is one of those things where you really shouldn't let money be an issue. Learning to save your life or a loved one's life from an attacker has no maximum value. But if money is an issue, you can always check into community group classes, just make the instructor is good. A lot of times police departments will give out fee training to the communities, it won't be as complete as learning from a school or instructor whose primary job is to get you good at the discipline, but it is a good start.
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