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The authors investigated the agreement between StepWatch3™ (SW3) and ActiGraph™ wGT3X+ monitors for measuring step-based metrics in patients with peripheral artery disease and older adults. In 23 patients with peripheral artery disease and 38 older participants, the authors compared the metrics obtained during an outdoor (400-m track) walking session (step count) and a 7-day free-living period (step count and 60/30/5/1-min maximal or peak step accumulation) using the SW3 (ankle) and the wGT3X+ (hip) with the low-frequency extension filter enabled (wGT3X+/LFE) or not (wGT3X+/N). During outdoor walking session, agreement was high, particularly for wGT3X+/LFE: correlations ≥.98, median absolute percentage errors <1%, and significant equivalence using a ± 15% equivalence zone or narrower. In free living, no wGT3X+ method was equivalent to SW3 for step count. The wGT3X+/LFE was equivalent to SW3 regarding all step accumulation metrics using a ± 20% equivalence zone or narrower, with median absolute percentage errors <11%. The wGT3X+/LFE method is the best option for comparisons with SW3 in peripheral artery disease and older adults. [ABSTRACT FROM AUTHOR]

Mammals walk in different directions, such as forward and backward. In human infants/adults and decerebrate cats, one leg can walk forward and the other backward simultaneously on a split‐belt treadmill, termed hybrid or bidirectional locomotion. The purpose of the present study was to determine if spinal sensorimotor circuits generate hybrid locomotion and if so, how the limbs remain coordinated. We tested hybrid locomotion in 11 intact cats and in five following complete spinal thoracic transection (spinal cats) at three treadmill speeds with the hindlimbs moving forward, backward or bidirectionally. All intact cats generated hybrid locomotion with the forelimbs on a stationary platform. Four of five spinal cats generated hybrid locomotion, also with the forelimbs on a stationary platform, but required perineal stimulation. During hybrid locomotion, intact and spinal cats positioned their forward and backward moving hindlimbs caudal and rostral to the hip, respectively. The hindlimbs maintained consistent left–right out‐of‐phase alternation in the different stepping directions. Our results suggest that spinal locomotor networks generate hybrid locomotion by following certain rules at phase transitions. We also found that stance duration determined cycle duration in the different locomotor directions/conditions, consistent with a common rhythm‐generating mechanism for different locomotor directions. Our findings provide additional insight on how left–right spinal networks and sensory feedback from the limbs interact to coordinate the hindlimbs and provide stability during locomotion in different directions. Key points: Terrestrial mammals can walk forward and backward, which is controlled in part by spinal sensorimotor circuits.Humans and cats also perform bidirectional or hybrid locomotion on a split‐belt treadmill with one leg going forward and the other going backward.We show that cats with a spinal transection can perform hybrid locomotion and maintain left–right out‐of‐phase coordination, indicating that spinal sensorimotor circuits can perform simultaneous forward and backward locomotion.We also show that the regulation of cycle duration and phase duration is conserved across stepping direction, consistent with a common rhythm‐generating mechanism for different stepping directions.The results help us better understand how spinal networks controlling the left and right legs enable locomotion in different directions. [ABSTRACT FROM AUTHOR]