Effects of wearing raised-heel insoles for 60 days on physical functions: focusing on adult males in their twenties

Background and Objectives: As men frequently use raised-heel insoles (RHIs) for a cosmetic purpose rather than a functional purpose in daily life, they are exposed to the risk of musculoskeletal disorders. The objective of this study was to evaluate the effects of wearing RHIs for 60 days on overall body functions and mechanical adaption.Materials and Methods: This study measured pelvic range of motion (ROM), balance, two-point discrimination (2PD), ankle joint ROM, lower back pain (LBP), muscle tone, stiffness, and decrement in male subjects in their 20s. Subjects wore RHIs (5 cm) for 8 h per day for 8 weeks (60 days). Measurements were conducted at 0, 30, and 60 days after the experiment began. Repeated-measures one-way analysis of variance (ANOVA) was performed to examine the effects of wearing duration (0, 30, and 60 days) on variables followed by a post-hoc test (Dunnett T3) when there was a significant difference.Results: Pelvic ROM decreased (p < 0.01), whereas static balance and 2PD increased (p < 0.001, p < 0.01, respectively) when the duration of wearing RHIs increased. The pelvic ROM on day 0 was significantly different from that on day 60 (p = 0.01). Static balance showed significant differences between day 0 and day 60 or day 30 (p = 0.000, p = 0.000, respectively). Dynamic balance, ankle joint ROM, and LBP did not differ significantly. The muscle tone of the plantar flexors (medial gastrocnemius) increased (p < 0.05), whereas decrement decreased (p < 0.05).Conclusions: It was found that wearing RHIs for a long time would adversely affect the human body. Wearing RHIs for a long time decreased pelvic ROM, whereas static balance and 2PD increased. It might have affected the overall body functions by increasing the muscle tone of the plantar flexors and worsening dynamic stiffness at the same time. The clinical significance lies in the fact that wearing RHIs for long durations would adversely affect the human body.