Abstract
This study evaluated the effects of a top-tier carbon plated shoe with highly responsive foam (CP-shoe) on changes in running economy (RE) and running speed at lactate threshold (LT) before, during, and after prolonged running. Ten male distance runners (half-marathon time: 75 ± 3 min) completed a series of tests. Initially, two graded treadmill tests were undertaken in a well-rested state while wearing either a CP-shoe or non-carbon plated shoe (NCP-shoe) to determine RE and LT-speed (LT(CP) and LT(NCP)). On separate days, participants then performed three 80-min runs in randomized order: twice at 95% LT(NCP) (14.7 ± 0.5 km·h(-1), once with each shoe) and once at 95% LT(CP) (15.2 ± 0.4 km·h(-1), CP-shoe only). RE, blood lactate concentration ([La(-)](b)), heart rate (HR), and perceived exertion (Borg scale) were recorded throughout. Each 80-min run was followed by a graded exercise test with assessment of RE and LT-speed. At matched external workload (95% LT(NCP)), the CP-shoe improved RE and lowered [La(-)](b), HR, and Borg compared with the NCP-shoe. At matched internal workload (95% LT specific to each shoe), the CP-shoe again demonstrated superior RE and lower HR. However, the time course of changes during the 80-min runs did not differ between shoes (i.e., no shoe × time interactions). Across all 80-min runs, LT-speed and RE improved postexercise, with the CP-shoe yielding higher LT speeds than the NCP-shoe (+0.5-0.6 km·h(-1)). In conclusion, the CP-shoe enhanced RE and reduced perceived exertion and [La(-)](b) compared with the normal running shoe during prolonged running, although the magnitude of changes over time was not different between shoes.