There also has to be objectives in a sport that make it competative, but competative for entertainments purposes. Rather than something like cheerleading which is genuinely just for entertaining people. But of course, cheerleading is a sport if there are two teams of cheerleaders performing for judges to be the best, that would be sport.
Also, further to coasterpimps comment. It's very hard to define a "creation" date for a sport like football, or something like playing catch for example, because these are such natural things to do for the body's own personal entertainment. Think back to medieval times and even further back than that, people would kick chicken carcasses around for fun. This could be construed as being football. But it wasn't football, because the sport has a defined set of rules that make it that sport. The first recorded inccident of a game of football with rules similar to that of today was at a school in Scotland in 1633.
Think about sports like wrestling and martial arts and things like that, these have been around as sport for many many thousands of years.