Sport photography;
When you learn how to shoot aircrafts speeding over 260 km per hour,  you may search other speedy photo subjects to be freezed in frames. Sport photography became an other interest for me after aviation photography. Just like using different setups while photographing  different types of aircrafts , you must learn the different set ups for every different sport brach. Besides you also have to learn the basic rules of the game. And just like in aviation photography you must be very carefull due to the spesific safety rules of the game you are photographing. 
Marathon, Icehockey, Swimming, Cycling, Flag Football, Tenis, Yachting were the branches i have photograped lately...
Any sport brach is in my scope to be photograped.
Let me show you "Your Struggle"