Surfing can be broken into several skills: paddling strength, positioning to catch the wave, timing, and balance. Paddling out requires strength, but also the mastery of techniques to break through oncoming waves ("duck diving", "eskimo roll" also known as "turtle"). Take-off positioning requires experience at predicting the wave set and where they will break. The surfer must pop up quickly as soon as the wave starts pushing the board forward. Preferred positioning on the wave is determined by experience at reading wave features including where the wave is breaking. Balance plays a crucial role in standing on a surfboard. Thus, balance training exercises are a good preparation. Practicing with a Balance board or swing boarding helps novices master the art.