Stride

The stride phase begins at the end of the windup when the lead leg begins to fall and move toward the target and the two arms separate from each other (Fig. 2.1C-E). The stride phase ends when the lead foot contacts the mound (Fig. 2.1E). A typical stride lasts from 0.50 to 0.75 second. Moderate activity from the elbow flexors is needed to control elbow flexion and extension. As the hands separate, the elbow flexors first contract eccentrically as the elbow extends and then contract concentrically as the elbow flexes near the completion of the stride. The elbow is flexed from 80° to 100° at lead foot contact.24 25 29 Minimal elbow kinetics and muscle activity are present during the stride phase (Table 2.1).20,24-26,28

FIGURE 2.1. Sequence of positions during the baseball pitch. (Adapted from Werner et al.24)
TABLE 2.1. Muscle activity during pitching, (plus or (minus) standard deviation)*

nt

Windup

Stride

Arm cocking

Arm acceleration

Arm deceleration

Follow-through

Elbow and forearm muscles

Triceps

13

4 (6)

17 (17)

37 (32)

89 (40)

54 (23)

22 (18)

Biceps

18

8 (9)

22 (14)

26 (20)

20 (16)

44 (32)

16 (14)

Brachialis

13

8 (5)

17 (13)

18 (26)

20 (22)

49 (29)

13 (17)

Brachioradialis

13

5 (5)

35 (20)

31 (24)

16 (12)

46 (24)

22 (29)

Pronator teres

14

14 (16)

18 (15)

39 (28)

85 (39)

51 (21)

21 (21)

Supinator

13

9 (7)

38 (30)

54 (38)

55 (31)

59 (31)

22 (19)

Wrist and finger muscles

Extensor carpi

radialis longus

13

11 (8)

53 (24)

72 (37)

30 (20)

43 (24)

22 (14)

Extensor carpi

radialis brevis

15

17 (17)

47 (26)

75 (41)

55 (35)

43 (28)

24 (19)

Extensor digitorum

communis

14

21 (17)

37 (25)

59 (27)

35 (35)

47 (25)

24 (18)

Flexor carpi radialis

12

13 (9)

24 (35)

47 (33)

120 (66)

79 (36)

35 (16)

Flexor digitorum

superficialis

11

16 (6)

20 (23)

47 (52)

80 (66)

71 (32)

21 (11)

Flexor carpi ulnaris

10

8 (5)

27 (18)

41 (25)

112 (60)

77 (42)

24 (18)

Adapted from DiGiovine et al.28

*Means and standard deviation are expressed as a percentage of the maximal manual muscle test. +n = number of subjects.

Adapted from DiGiovine et al.28

*Means and standard deviation are expressed as a percentage of the maximal manual muscle test. +n = number of subjects.

Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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