Characterization of foot-strike patterns: Lack of an association with injuries or performance in soldiers

Abstract

Objectives: Characterize the distribution of foot-strike (FS) patterns in U.S. Army Soldiers and determine if FS patterns are related to self-reported running injuries and performance. Methods: 341 male Soldiers from a U.S. Army Combined Arms Battalion ran at their training pace for 100 meters, and FSs were recorded in the sagittal plane. Participants also completed a survey related to training habits, injury history, and run times. Two researchers classified FS patterns as heel strike (HS) or nonheel strike (NHS, combination of midfoot strike and forefoot strike patterns). Two clinicians classified the musculoskeletal injuries as acute or overuse. The relationship of FS type with two-mile run time and running-related injury was analyzed (p ≤ 0.05). Results: The Soldiers predominately landed with an HS (87%) and only 13% were characterized as NHS. Running-related injury was similar between HS (50.3%) and NHS (55.6%) patterns (p = 0.51). There was no difference (p = 0.14) between overuse injury rates between an HS pattern (31.8%) and an NHS pattern (31.0%). Two-mile run times were also similar, with both groups averaging 14:48 minutes. Conclusion: Soldiers were mostly heel strikers (87%) in this U.S. Army Combined Arms Battalion. Neither FS pattern was advantageous for increased performance or decreased incidence of running-related injury.