Foot joint coupling variability differences between habitual rearfoot and forefoot runners prior to and following an exhaustive run

• Published in: Journal of electromyography and kinesiology 2021-04, Vol.57, p.102514-102514, Article 102514
• Main Authors: Seneli, Rhiannon M., Beschorner, Kurt E., O'Connor, Kristian M., Keenan, Kevin G., Earl-Boehm, Jennifer E., Cobb, Stephen C.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Biomechanical Phenomena - physiology; Exercise Test - methods; Fatigue; Female; Foot - anatomy & histology; Foot - physiology; Foot Joints - anatomy & histology; Foot Joints - physiology; Foot strike; Gait - physiology; Humans; Joint coupling variability; Male; Multi-segment foot model; Muscle, Skeletal - physiology; Physical Exertion - physiology; Running; Running - physiology; Young Adult
• ISSN: 1050-6411; 1873-5711
• DOI: 10.1016/j.jelekin.2021.102514

As joint coupling variability has been associated with running-related lower extremity injury, the purpose of this study was to identify how variability within the foot may be different between forefoot (FFS) and rearfoot strike (RFS) runners. Identifying typical variability in uninjured runners may contribute to understanding of ideal coordination associated with running foot strike patterns. Fifteen FFS and 15 RFS runners performed a maximal-effort 5 km treadmill run. A 7-segment foot model identified 6 functional articulations (rearfoot, medial and lateral midfoot and forefoot, and 1st metatarsophalangeal) for analysis. Beginning and end of the run motion capture data were analyzed. Vector coding was used to calculate 6 joint couples. Standard deviations of the coupling angles were used to identify variability within subphases of stance (loading, mid-stance, terminal, and pre-swing). Mixed between-within subjects ANOVAs compared differences between the foot strikes, pre and post run. Increased variability was identified within medial foot coupling for FFS and within lateral foot coupling for RFS during loading and mid-stance. The exhaustive run increased variability during mid-stance for both groups. Interpretation. Joint coupling variability profiles for FFS and RFS runners suggest different foot regions have varying coordination needs which should be considered when comparing the strike patterns.