Abstract: Using the methods of documentation, expert interview, questionnaire and experimentation, the paper chose 12 male teenage butterfly swimmers from the second and third tier teams in Shanghai as subjects and divided them into the experimental group and the control group. The experimental group received the water-land core stability strength training of “2-4-2” for two months while the control group did regular strength training. Before and after the intervention of the experiment, the subjects’ performances were tested and recorded. The performances include 8-bridge test, 15meters push-wall butterfly kick, 50 meters butterfly, 100 meters butterfly and performance in the last 15 meters section 100 meters butterfly and the average stroke rate, length and velocity. The study shows that the water-land core stability strength training can effectively improve the young butterfly swimmers’ performances.

Key words: Core Stability Strength, Physical Training, Butterfly Stroke, Teenager