Changes in the stride, walking speed and physiological cost index (PCI) before and after HAL use. The HAL suit increased the stride length in 4 of 16 patients (A). The walking speed increased in 4 of 16 patients while walking with the HAL suit, and this change persisted even while walking with the KAFO after removing the HAL suit on the following day. The walking speed markedly decreased in 12 patients while wearing the HAL suit (B). The PCI values clearly decreased after wearing the HAL suit in only 2 patients. In 11 patients, the PCI values apparently increased after wearing the HAL suit, but removal of the HAL suit led to a decrease in PCI values in 8 of 12 patients to levels equivalent to or below those observed before wearing the HAL suit (C).