Table 1 Muscle Onset, Duration, and Offset
Mean (SD) onset (ms)Mean (SD) offset (ms)Mean (SD) duration (ms)Serve motion (%)Range (%)
Supraspinatus−103.83 (50.98)262.17 (153.8)366.0 (112.7)5838–69
Infraspinatus47.05 (101.9)230.95 (113.6)183.9 (101.5)2818–31
Teres minor−214.75 (64.7)319.5 (66.2)534.25 (66.1)8177–91
Serratus anterior−286.98 (297.4)199.87 (128.7)486.85 (226.4)7439–89
Upper trapezius−234.45 (211.9)225.29 (186.5)459.74 (193.7)7039–92
Lower trapezius−119.7 (100.5)296.25 (195.5)425.95 (148)6246–71
Anterior deltoid−250.3 (194.8)170.1 (147.1)420.4 (164.5)6340–72
Posterior deltoid−157.8 (45.9)281.54 (97.4)439.34 (67.7)6754–77
  • Values expressed in relation to ball impact (T0). Activations prior to T0 = negative numbers. Activations after T0 = positive numbers.