RESUMEN
BACKGROUND: Because of the tremendous forces produced and the repetitive nature of baseball, players have shown various shoulder adaptations in strength and range of motion. However, no research has identified whether alterations occur in the blood flow to the dominant arm among competitive baseball players. METHODS: Twenty professional baseball pitchers and 16 position players participated. Measurements were taken on day 1 of 2 consecutive spring training seasons. Diagnostic ultrasound was used to measure blood flow of the throwing arm brachial artery. These measurements were taken in a standing position with the test arm resting at the participant's side and again with the test arm in a provocative shoulder position. Separate 1-way analyses of variance were conducted to compare blood flow between seasons (P < .05). RESULTS: In a resting position, the blood flow of the pitchers did not change from 1 year to the next (P = .48). However, blood flow of the pitchers in the provocative position significantly decreased after the first year (P = .009). The position players did not have any significant changes in blood flow for either arm position (P > .11). CONCLUSIONS: In a provocative shoulder position, the blood flow of pitchers significantly decreased after 1 competitive baseball season. These results indicate that after a competitive season, the blood flow to the upper extremity of pitchers may be compromised.