Change in Grip and Pinch Strength Over the Course of a Game in Professional Baseball Pitchers.

BACKGROUND

Baseball pitching injuries can be related to fatigue. Changes in grip and pinch strength over the course of professional baseball games are unknown.

HYPOTHESIS

Grip and pinch strength will decrease as the number of innings pitched increases; injured pitchers will have a lower grip strength than uninjured pitchers.

STUDY DESIGN

Prospective cohort study.

LEVEL OF EVIDENCE

Level 3.

METHODS

Minor league pitchers for 1 affiliate of a single organization were included. Changes in dominant and nondominant grip, and middle and index finger pincer strength were recorded pregame and after each inning, and compared between players who sustained a shoulder/elbow injury and those who did not.

RESULTS

Of 41 pitchers included, 6 sustained a shoulder (n = 2) or elbow (n = 4) injury during the study period. Average grip strength for all pitchers was 124.5 ± 17 lb pregame and increased slightly after the first inning (125.2 ± 17 lb), then declined slowly after the second (120.7 ± 18.5 lb), third (119.2 ± 24 lb), and fourth (113.1 ± 19.6 lb) innings. There was a slight uptick in grip strength in the fifth (118.5 ± 23.6 lb) and sixth (121.3 ± 21.8 lb) innings, but pregame levels were not reached. Evaluating uninjured and injured pitchers, the grip strength of injured pitchers was lower at all timepoints. As a percentage of uninjured pitchers grip strength, injured pitcher grip strength was 94.8% pregame, and 97.9%, 95.4%, 81.8%, 87.7%, 82.3%, and 74.5% after the first to sixth innings, respectively.

CONCLUSION

Dominant arm grip strength generally declined over the course of a game in professional baseball pitchers. Injured pitchers generally had weaker grip strength and a steeper decline in grip strength during games compared with uninjured pitchers.

CLINICAL RELEVANCE

Incremental loss of grip strength may increase injury risk in professional baseball pitchers.