I would like to learn a martial art that can help me learn to defend myself against singular and potentially multiple opponents. I was going for Krav Magar but I realized that I was taking it too far. I am 6" 4, I run half marathons and I'm working up to full marathons. I'm getting into doing half Ironman's(the iron man triathlons), and I've been gymming for a while. I'm also 16 in about two weeks. I have been through extensive physical and mental bullying and school (when I was shorter and unfit) and I have a mindset of needing to defend myself against everyone and I have realized because of that, going and doing Krav Magar probably isn't a good idea. I live in New Zealand and I need a martial art I can do that will let me defend myself without going too far. It can't have elements of spirituality in it (like karate) because my parents are Christian and I'm not allowed to do stuff like that. Thanks in advance.
You are a 16 year old male, tall, and physically in very good shape and improving all the time.
Your primary motivation for training in a martial art is to gain practical skill at defending yourself against bullies in your neighborhood and at school.
And pretty much any Eastern martial art is out of the question, because your parents might see it as threatening to your Christian upbringing.
I think based on all of what you said, I would recommend you look at 4 styles: Brazilian Jiujitsu, MMA, Boxing, and Muay Thai.
Any martial art can give you self-defense skills. But self-defense isn't fighting. Self-defense is about dealing with common scenarios that happen, such as someone getting you in bear hug, someone getting you in a side head-lock, someone grabbing your lapel and cocking back his other hand's fist ready to punch you, etc. These are techniques that are used to get you out of those situations, usually so you can run away immediately afterwards.
Whereas, fighting is the entire struggle from beginning to end. It's not just a collection of self-defense techniques that you string together to make a fight. Most of the fight has nothing to do with those techniques.
The thing is, you can learn hundreds of self-defense techniques and still not be prepared to fight. Learning to fight for real requires a different method of training, one in which you are forced to deal with someone who is not letting you do things to him and who fights back.
Which is why I gave you those 4 martial arts. Those styles have a proven track record for making skilled fighters, not just martial artists and theoreticians. Those styles all incorporate 1) liveness, and 2) resistance / pressure.
Liveness means that your partner in class is someone who won't just do the technique and stop, as if he's a robot. He's going to keep going. If he sees you are unbalanced, he's going to kick your legs out. If he sees you left your guard down, he's going to show a jab to your face. If you're doing something that begins with a wrist lock on him, he's going to pull his wrist out of the lock when he sees you don't really have it.
Go on YouTube and watch some martial arts demonstrations. Notice how after the one guy throws his punch or does whatever, he just stops. Then the instructor does one thing after the next, with his partner just doing nothing. It makes the instructor look like a god. Yet, anyone can look awesome when their partner has stopped moving and is just letting them do stuff. Instructors get a pass when they do this, because they can just say it was a demonstration, not real fighting. But these same instructors often don't go further than this in their classes. So it leaves students with an unrealistic expectation about the effectiveness of those techniques in actual fights.
Resistance and pressure testing is the second requirement. You need a partner who's going to use speed and force against you. They're going to really work at it to try to overcome you and win against you.
Putting both liveness and resistance together, what it will look like is your partner will not let you get away with anything and will keep coming at you relentlessly. You'll feel like it's a fight. If your stuff doesn't really work, you'll find out real quick. That will force you to get better. And when it does work, you will gain real confidence.
In martial arts that do not train this way, practitioners sometimes report getting into real fights and losing because they just froze. In that moment, they realized nothing has prepared them to actually fight. They know a lot, but there's a difference. They felt confident in their abilities going into this situation, but it suddenly vanishes the instant they realize they're lost. That's due to false confidence.
The next thing you'll notice about those 4 styles is that they're all sports. That may set off alarm bells in you. You don't want just a sport. You want a real fighting style. The thing is, these styles all have a set of rules mostly there to keep you from getting seriously hurt during training or competition. The idea is that you want to be able to go all out without hurting each other so much that you can't come back tomorrow. Because, if you're so hurt that you can't train for another 3 months due to broken bones or something, you won't be able to learn. The more training you get, the better off you'll be.
And if you wanted just one style that had the least set of rules and most freedom to do whatever you wanted (kick, punch, throw, choke, etc.), then that would be MMA. Muay Thai limits you to punches, kicks, elbows, knees, and a Thai clinch. Boxing limits you to just punches. BJJ limits you to grappling, no punches or kicks. But MMA lets you do everything.
MMA has rules, too. They're there to make sure people don't get seriously hurt.
And these days, you can find schools that just teach you MMA. Though, they may have classes in BJJ, Muay Thai, and Boxing separately, or they may try to incorporate drills from each of those other styles.
As for the religious / spiritual aspect, the only one of those 4 that might have some of that is Muay Thai. But it's very minimal and can easily be seen as ceremonial and not really required at all. You can meet with the instructor and just tell him what your situation is and ask if his style is compatible.
BJJ also has bowing, which many Christians frown against. But it's just there to show respect and for tradition.
You're absolutely safe with MMA and Boxing. There is no spiritual / religious component or aspect to these at all.
As for multiple attackers, just realize that you're not going to find any style that deals with those particularly well. Usually fighting one person is hard enough. Fighting 2, 3, or more is unrealistic.
If you do end up in a fight with more than one person, you'll want to make sure you take the approach of keeping distance from everyone. The moment someone forces you into fighting them, do whatever is necessary to extricate yourself and get back to being able to distance yourself. Then when you have distance, look for a way out and run. You don't need to fight to win. You need to fight only in order to get away.
Most would also suggest carrying a weapon as a "force multiplier" when things go badly, since you're outnumbered in a multiple attacker scenario. But at your age and in the scenario of bully defense, you're just going to end up expelled from school and thrown in juvenile detention if you even just show a knife in a fight on school grounds.
Finally, let me put this in perspective for you from someone who was in a similar situation in my high school years: You've got 2 or 3 more years of school before you're out of there. It seems like an eternity now, but when you're 30, you'll remember what you were thinking and how short-sighted it was.
These guys who are in your world right now are going to vanish the moment you graduate. You'll never see them again. Then you're going to be in a new environment with new friends who are actually nice to you and who come get you whenever they're going to do something.
The situation you're in now sucks. But it's not forever. Avoid the a-holes in your life. Devote all your mental real estate to improving yourself and being the kind of guy you would like others to be. If you do that, you'll be so much more successful in life than any of those guys who are mean to you now. In the end, you'll win.
Hope that helps.
The answer to "I need a martial art for self-defense" is usually "take a look at what's available and go for the one that spars the hardest". Without knowing what's available in your area, it's hard to provide proper counsel. Some style do have better track records than others, though, so we can make general suggestions.
However, you mention that you might not be allowed to train in the "best" martial art if it includes spiritual or religious elements. So let's look at the most recommended arts for self-defense, and eliminate the ones with these components.
Generally speaking, the most recommended striking arts for self-defense are going to be boxing, kickboxing and Muay Thai, with various branches of knockdown karate (such as kyokushin and all its derivatives) coming to a close second.
Of these, knockdown karate is often the most available but, as you've said, the mokuso (meditation) and the bowing present in karate are interpreted by your parents as being religious rituals. So, for the sake of this argument, we'll disqualify karate.
Muay Thai is a modern crowd favourite. It's efficient, it's powerful, and it looks cool. No one is doubting its effectiveness for self-defense. There is, however, the notion of the Wai Khru Ram Muay, a traditional dance meant to show respect to the teachers and the ancestors, and whose movements are heavily influenced by Buddhist faith. In pretty much every Muay Thai gym, this isn't going to be an issue. But if your parents want to be very strict about it and do some research, they might learn about it and come to the conclusion that Muay Thai has spiritual aspects (though that would be, in my humble opinion, just as nonsensical as interpreting the bowing and mokuso of karate as religious rituals).
So if you want to be extra safe, the best striking arts -for you- are probably going to be boxing and kickboxing. Both generally have great quality control, spar hard, allow you to compete to validate your training, and will teach you how to fight. If you can find a gym that trains one (or both) of those, you're set for striking.
If the early UFC has taught us anything, it's that a trained grappler will generally have the upper hand in a fight against an opponent that doesn't know how to grapple. As such, I'd definitely advise you to take up a grappling art at some point if self-defense is your main objective. And as far as grappling goes, the traditional recommendations are wrestling, BJJ, and judo.
Considering your spirituality requirements, I would probably disqualify judo and BJJ, for the same reasons as karate would be disqualified. Well, if BJJ is available to you, I'd probably take a look first, as there is currently a trend to evacuate some of the Japanese rituals that remain in the art. So you might be lucky and find a BJJ gym that won't infringe on your parent's faith. I've personally never seen a judo club that didn't bow and meditate, however.
So given the circumstances, I'd say your best bet would be, as far as grappling goes, wrestling. If you were in America, it would likely be available freely to your school but, sadly, it can be hard to find elsewhere (though it must obviously exist, seeing as most countries will send wrestlers to compete in the Olympics, but that's another story). If you can find it near you, do try it out.
Special mention to Sambo as well: it's basically Russian Judo, and it was developed on orders from Lenin, so you can generally be sure that there is nothing religious or spiritual left in there. I've never trained it myself, but I've sparred against sambo guys (I train Judo) and they were legit.
Mixed Martial Arts
Mixed martial arts are defined by their integration of techniques from different arts, and governed by a specific set of competition rules. There are many flavours of mixed martial arts going around, and some are more well known than others. There's UFC-style MMA, of course, which most people are familiar with. But then there's also stuff like sanda, shootboxing, combat sambo, kudo daido juku, gongkwon yusul, etc.
Of all of these, I'd say kudo daido juku and gongkwon yusul are the most likely to incorporate spiritual aspects (being derived from karate and hapkido respectively they involve the usual culprits: bowing and meditation). So let's disqualify them.
UFC-style MMA is often split into striking and grappling classes, with some "MMA" sparring sessions thrown in the mix. What is actually taught in most gyms will vary immensely from one instructor to another. Some gyms will focus on boxing/kickboxing for striking, others on muay thai, etc. For grappling, it's mostly BJJ and wrestling. Luckily, however, unless it's an actual BJJ/muay thai class, there isn't going to be any spirituality involved.
Combat sambo does seem like it could be interesting, as it's basically sambo with striking allowed, though I have absolutely no experience with it to form a proper recommendation considering your needs. I'd say try it out if it's available.
Seeing as you're in New Zealand, and thus closer to Asia, you might be lucky enough to have an easier time finding shootboxing gyms. Shootboxing is basically MMA without ground and pound (no striking once you hit the ground). It's very popular in Japan (though "niche", maybe), but very little elsewhere. If you can find it, it might work out very well for you. I do not believe there are spiritual elements involved here, either.
Sanda is what MMA could've been if it evolved mostly through Chinese Kung Fu. It's a combat sport that generally has a great reputation as far as effectiveness for fighting and self-defense goes. There is very little ritual involved (minimal bowing and salutes, basically the Chinese version of shaking hands), so I'd feel safe recommending it to you given your constraints.
In summary, if you can find UFC-style MMA, combat sambo, shootboxing or sanda, they are probably safe bets.
If you can only afford to train a single art, mixed martial arts are definitely the way to go, as they will teach you the basics of both striking and wrestling. If, however, money isn't an issue, picking one recommended striking art as well as one recommended grappling art will result in basically the same skill set, though you might have less opportunities to spar using both at the same time. Depending on availability and pricing, however, it's sometimes easier to train grappling and striking in separate schools.
I do, however, want you to consider that there are likely other means for you to solve your current issues. Let's be honest... of all the people that take martial arts for self-defense, only a tiny minority of them ever actually use it for that purpose. De-escalation tactics, situational awareness and better decision making will get you out of more fights than martial arts ever will. And it those fail, running and cardio will probably get you out of there with less risks to your health than martial arts. In fact, one could certainly argue that you are more likely to get injured while practicing martial arts than in a street fight, and they'd probably be right, statistically speaking.
As someone who trains for Ironman triathlons, odds are that you can outrun anyone that's big enough to feel like they could intimidate you (you are pretty tall, after all). If running was considered a martial art, it would literally be my #1 recommendation to you.