Supplementary Material for: Differences in foot morphology across age groups for women active in sport

Introduction: Foot morphology in the general population has been shown to change with age and active older adults have reported a need for wide-fitting footwear. Methods: This study recruited 374 women active in racket sports and team sports in the United Kingdom who had their feet scanned while 50% weight bearing. Participants were grouped into 10-year age bands ranging from 18-29 years to 70-79 years. Data analysis was performed on the widths, heights and circumferences of participants’ right feet normalised to foot length, as well as an assessment of hallux valgus angle and deformity. Results: The 18–29-year group had significantly smaller in measures of foot width, ball of foot circumference and short heel circumference (p<0.05, η2 =0.042- η2 =0.056) compared to the older groups. The foot dorsum height and circumference at 50% foot length were significantly less in the oldest age groups compared to the middle age groups (p= 0.0001, η2 = 0.055 and p= 0.0007, η2 = 0.044 respectively). There was some evidence of increased hallux valgus deformity with age. Conclusion: Designers and manufacturers of athletic footwear should be aware of the changes in footwear morphology with age in order to provide more inclusive footwear.