How did Inge de Bruijn, Pieter van den Hoogenband, Michael Klim, Dara Torres, and the rest swim so fast in the 2000 Olympics? How are swimmers continuing to get faster - and what will we see in Greece at the 2004 Olympics?
There are many ways for a swimmer to cover a set distance in less time. Faster turns, a better start, decreasing resistance (through technique or suit materials), or a more propulsive kick could all help to improve a performance. Two other ways for a swimmer to go faster that involve the actual arm action of a swimmer are to increase the stroke rate (while maintaining the distance per stroke), and to increase the distance each stroke takes them (while maintaining the same rate). I think these fast, sprint-distance swimmers have found a way to maximize the distance covered per stroke while maintaining (or even increasing) their stroke rate. Some of the things they do could be applied to other distances, and be used by other swimmers, too.
Swimming is not an isolated body part sport; what your head is doing while you are kicking has an effect on your body and arm action. These ideas have been studied and tested various times, and it seems that the experts are still not exactly sure what is the single best way to swim freestyle. There are general ideas, but nothing that can be called the single best way. From coach to coach, and from author to author, you may hear slightly (or massively) different ideas on what comprises good freestyle technique. But when Inge de Bruijn and Michael Klim swam freestyle, I see similar things. According to de Bruijn's coach, this should be the case; he wanted de Bruijn to have the same basic technique as Klim. A few of the technique points I think I saw include a straighter arm recovery, a more pinky first entry, a fairly straight high elbow pull pattern, and more shoulder than hip roll.