There are certain Oriental martial arts that have become popular in the country, and all because of mixed martial arts venues or shows. For things like muay thai Dallas there are any number of school systems and the experts that provide instruction. For instance, the school in Dallas will have both Thai and American experts.
The tradition is also widespread enough in the Far East to have many practitioners there. Though it might work better with importing masters from this region, there are also many Americans who have mastered the art. And these provide the exact same training from the classical tradition here.
In fact they might even be stricter as compared to the Oriental masters. These may have other forms of disciplines incorporated but the association governing this art worldwide is strict about rules that are followed here. This means they are going to follow formal uniform rules, and the moves and behavior in this form.
You might want to become a practitioner through the means of schools that offer training. In this sense there can be a number of reliable and good ones in Dallas that could help. And these may be the venue or your home gym where you can practice your discipline all the time along with friends who are learning and training.
Most times there will be need for the students to be aware of the Oriental nature of the sport. Thailand is a country that is full of Buddhist traditions that have been incorporated into the art form. This means that there might be meditative techniques that are used although Muay Thai differs from those that come from Japan and China here.
It is more of a secular art that takes practicality as its main point of reference in training. That means that you have to be practical about training too. Which means that you learn directly any move taught and apply this with the necessary force and skill, so that you earn whatever distinction there is in this part of this process.
The system is geared towards kicking mostly, but it incorporates the complete range of defensive postures open to the human body. The Thai science or method is excellent in leg movements though, and usually favors this part of the body. That means that being in this discipline gets you at least really good legs that can last long.
The stamina for the practice and sparring is developed through training. Diet is important here, but there is no special one related to the program or the art. There is a lot of economy in the method and there is a certain hierarchy in the system for grading and there are personal best levels to accomplish.
The aim of this program though is to provide you with excellent defensive postures and the body with which to follow through with these. You could contact the masters or krus of the schools in Dallas and ask for details. Or you could go directly to the venue and look around.