A multiple repeated sprint ability test with four changes of direction for badminton players (part 2): predicting skill level with anthropometry, strength, shuttlecock and displacement velocity.

The goal of this study was: (i) to assess general and specific lower and upper limb force, shuttlecock velocity, displacement ability and the anthropometric characteristics of badminton players at five skill levels, and (ii) to predict individual players' number of points. We divided 83 participants into groups of novice (n=15), intermediate (n=16), skilled (n=23), highly skilled (n=14) and elite (n=15) players. The number of points scored for each player performing tournaments (excluding novices) during the entire season was used as a continuous and dependent variable after logarithmic transformation for correlational study. Anthropometric measurements of height, mass, percentage of fat and muscle were recorded, along with shuttlecock maximal velocity during smashes. Upper limb power and lower limb force were recorded during jumps and handgrip strength. We also assessed players' ability to move quickly around the court through an on-court multiple repetition sprint ability in badminton (MRSAB) test with four changes of direction. All variables were combined in a multiple regression model. The main findings were that the major contributor to skill level is shuttlecock velocity (r=0.86), the time taken to move during the MRSAB test (r=0.85) and the squat jump height (r=0.53). Anthropometric factors contribute only a little to the individual score point (2%). Finally, the multiple regression model reveals that log(number of points)= 4.91 + 0.042 x Shuttle velocity - 0.029 x MRSABTime - 0.001 x Squat Jump height, with r=0.86 and a relative respective contribution of each variable of 86%, 13% and 1%.