OBJECTIVE: Shock-absorbing insoles (SAIs), compared with usual insoles, were hypothesized to result in larger increases in pressure pain threshold (PPT) after 3 weeks of use. BACKGROUND: Shock-absorbing insoles can decrease self-reported pain among young soccer players training on artificial turf. However, nothing is known about the underlying changes in pain sensitivity assessed by PPT. METHODS: Seventy-five players were included from the youth teams of under 15, under 17, and under 19 years of age, playing for the Aalborg Boldspilklub (AaB) professional sports club. After a randomization stratified by team and age, players were divided into 2 groups, one that received SAIs and a control group that used their usual insoles. Assessments were made in both groups after 3 weeks of training on artificial turf (baseline) and 3 weeks later (follow-up). The primary outcome was change in PPTs from baseline to follow-up, with PPTs measured over 13 locations on the plantar surface of the foot, leg, and low back of the nonpreferred kicking leg. RESULTS: A significantly larger increase was found in PPTs from baseline to follow-up for the SAI group compared with the control group (mean difference 62 kPa; 95% confidence interval (CI) 40 to 85 kPa). The PPTs increased significantly more among the SAI group compared with the control group (p < 0.05) for the abductor digiti minimi (mean difference 82 kPa; 95% CI 6 to 157 kPa), tibialis anterior (mean difference 125 kPa; 95% CI 20 to 230 kPa), medial gastrocnemius (mean difference 83 kPa; 95% CI -6 to 171 kPa), and erector spinae (mean difference 86 kPa; 95% CI -17 to 188 kPa). CONCLUSION: The use of SAIs resulted in increased PPTs after 3 weeks of training on artificial turf compared with controls, suggesting a protective role of SAIs in pressure sensitivity and pain perception.

Full text (sometimes free) may be available at these link(s):      help

• DOI
• PubMed
• PDF locator
• publisher