You need to stop what you are doing because you are not doing it right. While I am all for supplemental training, just doing some exercises without thought to form and correctness is in the end detrimental to your health. It is very obvious you did not do any research into what is proper strength training. If you had you would have known that the traditional situps do not work the abs very much and are very bad for your lower back. You would also know that exercise tears down muscle fiber and it is the rest you give your body that builds up muscles. I bet you've been working out the same muscle groups without and rest days in between and that means you are actually losing and weakening your muscles because they were not given time to regrow/reheal.

If you want to workout, do it smart. Read up on what is proper form and what is the right amount (or frequency) of workout needed to build strength.

Personally, I see no reason why you should wait to start your martial art lessons. There is no reason why you cannot do your strength training and take lessons at the same time.

I'm going to urge you to just start, but more on that later.

If you must then condition smartly. Conditioning is great, but you have to either throw in a rest day in there or decrease the level of intensity. Also just keeping up with exactly the same workout every time makes you plateau. It means that you will see benefits at first, but your body will get used to it and you won't really see as much benefit. You can increase the weight or rep to change things up a bit, but it won't be enough to get out of the plateau. What you are going to have to do is change up the workouts every now and then. Best way is to go is to research on athletic conditioning and find out how it works and learn more work outs. If that sounds like too much work then you can try the crossfit website's work out of the day and follow that schedule. If crossfit is not your thing then there are also free youtube channels that gives you daily workouts.

Also on stretching. You can't rush it or you might tear something, and if you do then you'll have to sit out of any training for weeks. Just doing regular amount of stretching everyday is good enough. Don't keep pushing yourself until you are sore even after stretching.

As I stated in the beginning just join a class. If you have twins and have one start the class right away and have the other one work out first and join the class half a year later, then the one that joined right away will be better at the art than the gym rat by the end of the year. Also the class might teach you special conditioning method that works best for that style, which might be better than all around conditioning methods that is offered elsewhere mentioned above.

just start training under a qualified instructor. there is no need to prepare and procrastinate the issues, all that will come with you training.

find an good instructor in a style you like, the style is not important what is important is the quality of the instructor

I would suggest that Kokoro is correct. Stop putting off your training. Martial arts is a journey and you need to take that first step. You will learn to condition your body over time.

I want to start learning Martial Arts. I'm still only 15, but I've set my mind on it, and I know it is something that takes a lot of effort and time, which I'm willing to put it..

But before I even start, I want to begin preparing myself for it. Currently, I have two goals until I start to go to Karate Classes as a start. I know I don't need them to start basic martial arts, but I know they're useful anyway.

Firstly, I want to become much stronger. Not really specific, but it's just a fact.

Secondly, I want to become Flexible.

Thirdly, I need to increase my pain resistance (Holy crap, it's so low at the moment, even though I don't feel like crying, I can bang my head on a shelf and well up. I'm not about to cry or anything, but how are other people meant to know that..)

For the First thing, I am training pretty hard considering it's like my fourth day. I've been doing about 200 pressups a day, 150 situps a day and lifting really light weights (They must be like 2kg or something). What would you say I should move up to? I think 8KG sounds about right, considering I can do 50 2kg curls and hardly be tired from it.

For the second thing, If I stretch my legs out to the point to where they start to hurt from being too stretched out, and keep them there for extended periods with my own will, will I start to become more flexible? This will also solve problem number 3, as it hurts quite a bit, but it will be worth it.

Thanks a lot for any answers.