The object of modes is to give the photographer the best possible chance of getting an "acceptable" picture in a given type of situation based on a number of assumptions made by the manufacturer. For example, sports mode assumes you want to freeze what will likely be fast action in situations where lighting conditions may be less than ideal - hence a high ISO to allow as fast a shutter speed as possible.
P mode is different is so far as P mode won't change ISO and is set according to the lens in use and whether or not you are using flash. So, in P mode, the shutter speed will be set to a high speed when using a telephoto, a lower speed when using a wide angle. Sport mode will keep a high shutter speed regardless of the lens (subject, of course, to available light).
IMHO program modes should be avoided. At best using them takes a lot of creative control from the photographer, at worst, you can have a situation of the photographer fighting the camera and failing to understand why he/she can't get the picture they want.
Program modes will
produce an acceptable result a high proportion of the time, but are much less likely to produce the optimum
result in a given situation. And sooner or later, they will bite you by doing something entirely logical to the camera's little brain ... but not what the photographer wanted.
To avoid surprises, learn the principles of photography and stick to the TV
or Manual modes.
Colin K. Work, Pixstel