Table 2. Timing (mean ± SD) of key events expressed as time (s) prior to/after impact during the tennis forehand of elite and high performance players in the cross court and down the line (DL) situation. The variables on the left column are listed in order of their peak values during the forward swing of the elite players.
   

Elite (n=6)

    

High Performance (n=7)

  
  Variable

Cross

Dl

Mean

Cross

DL

Mean
  Max. hip alignment angle

-.253 (.086)

-.232 (.051)

-.243 (.068)

-.235 (.046)

-.236 (.034)

-.236 (.039)
  Max. shoulder alignment angle

-.234 (.051)

-.228 (.046)

-.231 (.046)

-.213 (.037)

-.214 (.027)

-.214 (.031)
  Max. separation angle

-.179 (.077)

-.158 (.082)#

-.168 (.077)

-.151 (.020)

-.145 (.020)#

-.148 (.019)
  Max. racquet rotation angle

-.157 (.047)

-.135 (.037)

-.146 (.042)

-.135 (.047)

-.131 (.040)

-.133 (.042)
  Max. hip linear velocity

-.100 (.048)

-.093 (.049)

-.097 (.046)

-.109 (.070)

-.116 (.062)

-.113 (.064)
  Max. pelvis angular vel.

-.076 (.008)

-.074 (.009)

-.075 (.008)*

-.091 (.013)

-.095 (.012)

-.093 (.012)
  Max. rear leg extension velocity

-.071 (.035)

-.066 (.040)

-.069 (.036)

-.081 (.032)

-.101 (.024)

-.091 (.029)
  Max. trunk angular velocity

-.058 (.002)

-.056 (.005)

-.057 (.004)*

-.074 (.012)

-.076 (.011)

-.075 (.011)
  Max. wrist extension angle

-.057 (.011)

-.053 (.011)

-.055 (.011)

-.054 (.010)

-.058 (.014)

-.056 (.012)
  Max. shoulder linear vel.

-.045 (.008)

-.045 (.009)

-.45 (.08)*

-.060 (.016)

-.062 (.017)

-.061 (.016)
  Max. elbow linear vel.

-.040 (.006)

-.037 (.004)#

-.039 (.005)

-.042 (.005)

-.038 (.008)#

-.040 (.007)
  Max. wrist linear vel.

-.038 (.005)

-.035 (.005)#

-.037 (.005)

-.041 (.004)

-.038 (.005)#

-.040 (.004)
  Max. racquet head horizontal velocity

-.003 (.000)

-.002 (.001)

-.002 (.000)

-.003 (.001)

-.003 (.000)

-.003 (.001)
  Impact time (s)

.263 (.094)

.256 (.078)

.259 (.082)

.252 (.065)

.259 (.055)

.256 (.058)
  Max. shoulder internal rotation velocity

.025 (.007)

.023 (.014)

.024 (.011)

.020 (.014)

.027 (.012)

.024 (.013)
  Max. elbow extension velocity

.031 (.040)

.040 (.027)

.035 (.033)

.014 (.051)

.010 (.052)

.012 (.049)
  Max. racquet head vertical velocity

.038 (.006)

.040 (.006)

.039 (.006)

.033 (.009)

.033 (.008)

.033 (.008)
* Elite group significantly different from High Performance group: pelvis (F = 9.857, p =0.009, η2 = 0.473), trunk (F = 13.526, p = 0.004, η2 = 0.552); tendency: shoulder (F = 4.968, p =0.048, η2 = 0.311). # Main shot effect for DL shot: elbow (F= 86.182, p = 0.000, η2 = 0.887); tendency: separation angle (F = 5.136, p = 0.045, η2 = 0.318), and wrist (F = 4.989, p = 0.047, η2 = 0.312).