Energy Return And Midsole Displacement In Advanced Running Shoes Using Male And Female Loading Profiles

Advanced running shoes (ARS) constructed with highly cushioned yet resilient midsole foam embedded with a carbon plate produce higher energy return and midsole displacement than traditional running shoes (TRS). Most research has studied these phenomena using the force profile of elite male runners. However, there is a need to examine the interplay between the plate and midsole technologies and how they influence energy return and midsole displacement in female runners. PURPOSE: To determine whether energy return and midsole displacement differ between male and female loading profiles. METHODS: We tested ten left male and ten right female shoes (2 ARS and 8 TRS). Each shoe was subjected to a series of five forefoot compression tests to measure the midsole displacement and energy return. The female protocol consisted of an input pulse of 1.4kN peak force over a duration of 170 ms, while the male protocol used a 2kN input pulse over 185 ms. We used an independent t-test to compare differences between loading profiles. RESULTS: There was no difference in energy return between male and female loading profiles in ARS but there was a significant difference in midsole displacement (11 ± 1.05 in male vs 8.5 ± 1.58 mm in female, p < 0.001). Male and female loading profiles had a similar pattern in TRS with no statistical difference in energy return but a significant difference in midsole displacement (7.88 ± 1.47 in male vs 6.75 ± 1.2 mm in female, p < 0.001). The midsole displacement was greater in ARS compared to TRS with both the male and female protocols, while energy return was also greater in ARS compared to TRS with both the male (80.6 ± 0.7 vs 69.7 ± 5.81 mm, p < 0.001) and female (81 ± 1.05 vs 69.38 ± 5.48 mm p < 0.001) protocols. CONCLUSION: Our results support previous findings of greater midsole displacement and energy return in ARS compared to TRS. The greater midsole displacement in ARS with a male loading profile vs a female profile while yielding similar energy return values suggests that gains might be made in ARS materials and construction to optimize female running performance. Further research is necessary to explore optimal midsole displacement values in female-specific ARS.