ArticleSports health
Is Workload Associated With Hamstring and Calf Strains in Professional Baseball Players? An Analysis of Days of Rest, Innings Fielded, and Plate Appearances.
Article in Sports health. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.
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Who cites it
4 citing papers in PubMed, 5 citations in OpenAlex.
- Major League Baseball Health and Injury Tracking System (HITS): A Review of MLB Injuries Documented in the HITS Database Since Its Inception.Orthopaedic journal of sports medicine · 2026Review
- Epidemiology, Performance, and Return to Sport After Rib Fracture in Professional Baseball Players.Orthopaedic journal of sports medicine · 2026Article
- Characteristics Associated With Noncompliance of Current Pitch Smart Guidelines in High School Baseball Pitchers Throughout the United States.Orthopaedic journal of sports medicine · 2023Article
- Article
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Authors and funding
6 authors at 4 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe influence of player workload on hamstring and calf injuries in professional baseball players remains unknown. HYPOTHESIS: Increased workload would significantly increase hamstring and calf strain injury risk. STUDY
designCase-control. LEVEL OF EVIDENCE: Level 3.
methodsAll professional baseball players who sustained a hamstring or calf injury between 2011 and 2017 were identified using the Major League Baseball (MLB) Health and Injury Tracking System (HITS). A separate player usage dataset was used to determine workload. We then compared these variables between player games 2, 6, 12, and >12 weeks before a documented calf strain to player games from a noncalf injury control group. In a paired analysis, we compared the acute workload (2, 6, and 12 weeks) before injury with the injured player's workload >12 weeks before injury.
resultsThere were 175 unique calf strains (71% occurred in position players) and 1042 unique hamstring strains (97.8% occurred in position players) documented in the MLB HITS database from 2011 to 2017. In all time periods, position players with fewer days rest, more innings fielded, and more plate appearances were associated with a higher risk of subsequent hamstring and calf strains. Having only 1 day rest was associated with a 2.08-fold increase in percentage of players who sustained a subsequent calf strain compared with those with 4 days rest. Position players with >5 days of rest had a 4.03-fold decrease in percentage of players who sustained a hamstring strain compared with players with 1 day rest. Position players who fielded >9 innings per game had a 2.01-fold increase in percentage of players with a subsequent calf strain and a 3.68-fold increase in percentage of players who sustained a subsequent hamstring strain compared with players who only fielded 1 innings per game.
conclusionPosition players with fewer days rest, more innings fielded, and more plate appearance per game had an increased risk of sustaining a hamstring or calf injury. CLINICAL RELEVANCE: Increased workload had a direct relationship with risk of hamstring and calf strains in professional baseball players. Teams should consider more days rest for position players to avoid calf injuries.
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