| Abstract ID |
| 20260131 |
| Category |
| Sports Medicine: Epidemiology and Injury Prevention |
| Preferable Presentation |
| Both |
| Title |
| THE RELATIONSHIP BETWEEN HIGH METABOLIC LOAD (HML) DISTANCE AND HAMSTRING INJURY SEVERITY IN ELITE ATHLETES |
| Author |
|
| Presenter |
| Worrawat Thananchai |
| Abstract |
| Background: Hamstring strain injuries (HSIs) remain a significant burden in elite sports, often categorized by clinical grading via imaging. While GPS-derived workload monitoring is standard practice for injury prevention, the specific relationship between metabolic loading intensities and the resulting clinical severity (Grade I vs. Grade II) is not fully established. Objective: To investigate the differences in absolute metabolic volume and relative workload distribution between Grade I and Grade II hamstring injuries in professional athletes. Study Design & Methods: A retrospective longitudinal analysis was conducted on 28 professional athletes (Grade I: n=15; Grade II: n=13). GPS-derived metrics, including High Metabolic Load (HML) distance, sprint counts, and the Acute:Chronic Workload Ratio (ACWR), were analyzed for the session in which the injury occurred. Statistical analysis utilized independent t-tests to compare means across grades and Cohen’s d to determine effect sizes. Results: A statistically significant difference in absolute HML distance was observed between injury grades (593.6m vs 756.1m, p < 0.01). This represents a large effect size (d = 1.05), indicating that Grade II injuries are associated with significantly higher metabolic demands. In contrast, the number of absolute sprints did not significantly differentiate between Grade I and Grade II injuries (p = 0.36). Longitudinal analysis of the lead-up to injury revealed that Grade I injuries were more frequently associated with a "Taper Failure" on the day before injury (MD-1), characterized by a peak ACWR of 1.41 ± 0.85, whereas Grade II injuries were characterized by sustained exposure to high absolute HML volumes. Conclusions: High Metabolic Load (HML) distance is a superior marker for differentiating hamstring injury severity compared to traditional sprint counting. These findings suggest two distinct mechanical paradigms: Grade II injuries are driven by high absolute metabolic volume (Mechanical Overload), while Grade I injuries are more closely linked to relative loading errors and insufficient tapering. Practitioners should prioritize position-specific HML thresholds over sprint counts to more accurately assess the risk of high-grade structural failure. |