After a year of intense exercise, I ate very little and was healthy. Why haven't I lost weight at all?

Some people are like this. Fat is burned by the body. But some of them are converted into other substances and stored in the body. In your situation, there is no need for high-intensity exercise. As long as you exercise moderately every day. A reasonable diet and balanced nutrition will do. Some people are not that fat. This is not easy to reduce. People who are puffy lose weight relatively better.