Martial arts is a broad term that describes several combat sports; boxing, fencing, judo, and tae kwon do may be the best known because they are Olympic sports, but there are hundreds of types of martial arts. Each art is diff erent, but most involve strength, fl exibility, and agility, and some also include explosive movements. Each art requires a strong level of mental and physical fi tness. Many have weight classes, and some martial artists use a variety of methods to make weight. Participants in some competitions, such as judo or tae kwon do, compete several times over the course of a day. Learn more about the sports at the USA Dojo website (www.usadojo.com).