Sprint Mechanics Predict Hamstring Injury Risk in Elite Footballers
HSIs now account for nearly 1 in 4 injuries in pro football and have doubled in the last 20 years in professional football (thats soccer in the USA).
These injuries not only sideline players but cost teams millions of dollars and affect team performance.
While biomechanics have been suspected contributors to HSIs, no prior study has clearly linked sprint mechanics to future injury risk until now.
Can suboptimal sprint running mechanics predict hamstring strain injuries in elite footballers?
What did the researchers do?
Study Design
- 126 elite male footballers from 8 English clubs were followed over 6 months.
- Athletes completed maximal 35-m sprints, which were filmed and assessed using the Sprint Mechanics Assessment Score (S-MAS).
- Hamstring injuries (retrospective and new) were tracked by club medical staff.
Sprint Mechanics Assessment Score (S-MAS)
- Video-Based Tool: This slow-motion video (240 fps) tool assesses sprinting techniques in the field.
- 12-Point Checklist: Evaluate key movement features like pelvic tilt, trunk rotation, leg extension, and foot placement.
- Higher Score = Worse Mechanics: Each point reflects a suboptimal sprint pattern that may increase injury risk.
What were the results?
Players with higher (worse) S-MAS scores were more likely to:
- Have had a previous sprint-related HSI and sustain a new sprint-related HSI during the 6-month follow-up.
- There was a 33% increased risk of future sprint-related HSI (after adjusting for age and injury history) for every 1-point increase in S-MAS.
- An S-MAS cut-off of 5.5 had 78.6% sensitivity and 65.4% specificity
What does this mean?
- Sprint running mechanics are now prospectively linked to injury risk.
- S-MAS provides a practical, field-based screening tool for identifying at-risk players.
- Suboptimal mechanics may persist even after rehab, suggesting biomechanical quality is not being adequately restored.
Limitations
- Training loads weren’t directly monitored.
- S-MAS hasn’t been validated against gold-standard 3D motion capture.
- Players came from multiple leagues and were followed at different season phases.
- Only elite male footballers were studied.
Coach's Takeaway
- Use S-MAS or similar tools to screen sprint mechanics in-season routinely, especially if you are dealing with HSI.
- Address biomechanics holistically, alongside eccentric strength, fascicle length, and load management.
- Incorporate sprint technique coaching during injury rehab.
