Kieran Healey's joke post about Olympic sports has stirred up some interesting comments in the comments thread about what a sport is, really, and what kind of sports make good Olympic sports.
The current Summer Olympics have just over three hundred events spread across twenty-six sport classifications. Both of these numbers vary somewhat from Olympics to Olympics; for instance, golf and rugby were once sports on the list, are currently not contested, but will be back on the list in the next Olympics. The sports classifications are:
Team Athletic Sports
Some of these are more arbitrary than others, of course. Athletics, for instance, is a mix of sports and currently has forty-seven different events, including running, walking, jumping, and throwing events of various kinds. Yes, there is such a thing as Olympic walking; it has been one of the constant core Athletics events, in fact, and it's actually one of the most gruelling sports. You visibly have to have one foot on the ground at every moment, but it's a race, so you have to move as quickly as possible, and the combination forces you to move your hips like crazy. What makes them gruelling, though, is that they are very long events; the longest event in the Olympics is the men's 50k walk, which requires you to walk as fast as you can for hours, observing correct form for the entire time.
One of the suggestions in the "Crooked Timber" comments was that Olympic sports should be confined to the quasi-martial variety, i.e., those having a clear historical link to martial training. This would preserve all the traditional Olympic athletic sports (athletics, pentathlon, triathlon), the martial arts (wrestling, judo, taekwando, boxing), the stylized weapon sports (archery, fencing, shooting), and at least one, probably all, of the equestrian sports (dressage originated as martial training). There would be gray areas, like rowing and swimming. Team sports, gymnastics, and cycling would tend not to be represented at the Olympic level under this criterion, although parts of gymnastics might be gray areas. Part of the reason for this is that while most of the very old sports are derived from martial training, most of the newer sports were invented in order to be forms of purely athletic exercise. What we think of as gymnastics for instance, was invented in the eighteenth century as a form of school exercise for boys. Education reforms were very popular in the late eighteenth and early nineteenth century, and one of the reforms was the idea of physical education. Gymnastics is quite literally a stylized version of what school P.E. was a hundred fifty years or so ago. Team sports in general have tended to be created for play, not training; in general they tend not to be good even for general atheletic training, much less military training -- for instance, there's nothing that basketball really trains you for. The basic athletics sports -- foot races, jumping, throwing -- train overall physical ability, while combat and weapon sports train for, or could train for, specific martial skills. Basketball, soccer, and handball are really just odd and complicated mixes of skill that exist in order to be odd and complicated mixes of skill, challenges for whiling away the time.
A little known fact about the Olympics is that it used to have art competitions as well; in fact, the founders of the modern Olympics considered such competitions a very important part of the Olympics. The arts in question had to be Olympics-related, but they even had medals and everything. This gives you some fascinating quirky cases, like Walter Winans, who won two Olympic gold medals (one in shooting, one in sculpture) and is one of two individuals in Olympic history who received Olympic medals for both sports and art (the other being Alfré Hajós, who received the first gold medal in swimming and a silver in mixed architecture). The art competitions were eventually done away with (in 1948) because of the organizational difference between sports and arts: sports have governing bodies, while the arts never did, which made art competitions massively more difficult to organize and host. This is, incidentally, one of the reasons chess keeps coming back as a possible candidate for an Olympic sport despite the widespread view that it is not really a sport: it has a governance organization like a modern sport. Or in other words, even though it is not an athletic event it is institutionally indistinguishable from athletic sports.