Surfing is one of the hardest sports since you need to balance your weight while you are aboard your surf board. It is not easy since the wave keeps slamming unto you. Also, balancing on water is not easy since you would fall under if you can't.
This game is about a car that is surfing on a train. Don't worry about balancing since that is not the objective of the game. The idea here is to get to the finish line as fast as you can. There is no minimum time frame as you just need to cross that finish line. Grab as many coins as you can while you are on your way. You can use the money to upgrade your car.