Muscular Christianity is the concept that participating in vigorous sports/exercises builds character. I have to say that I 100% believe in this concept and think that it really does reign true. I do believe that participating in sports builds character, whether it is a recreational sport, or if it is in a league for a title, playing a sport is going to help people build character. People have always said that winning proves who is the best, but losing builds character and I do feel that this is true. You learn valuable lessons when you lose.
You learn about yourself and others and you learn how people react to different events in their life, and how they are going to handle adversity. I cant say 100% that athletes have better character then non-athletes because many people who are non athletes have been through many things in their life that would cause them to grow and mature. People may have been in the army, have grown up in problematic families, or have been through tough times in their lives that would help to build their character up.
People are going to have different lives growing up, and these lives are all going to engrain different characteristics into these people. Characteristics are only going to come about however, with how people choose to showcase them to others. As for whether or not I think ones character is proportionate to the time and level they have played, I do find that to normally be true. I feel that the longer one has played, and the more they have been through, the more character they are going to build and the more mature in the situation they are going to be.
I know that when I would lose in hockey, I would hate it, and be very down on myself when I was younger, but now that I have been through it many times I have built up character to be able to handle the loss, and push it aside and get ready for the next game, or to talk to people after the loss and not be mad and take it out on them. You are not born with character, you build it over time!