The aim was to compare the effectiveness of dual-task training (DTT) compared to single mobility training (SMT) on dual-task walking, mobility and cognition, in persons with Multiple Sclerosis (pwMS). Forty pwMS were randomly assigned to the DTT or SMT groups. The DTT-group performed dual-task exercises using an interactive tablet-based application, while the SMT-group received conventional walking and balance exercises. Both interventions were supervised and identical in weeks (8) and sessions (20). Nine cognitive-motor dual-task conditions were assessed at baseline, after intervention and at 4-weeks follow-up (FU). The dual-task cost (DTC), percentage change of dual-task performance compared to single-task performance, was the primary outcome. Mobility and cognition were secondarily assessed. Mixed model analyses were done with group, time and the interaction between group and time as fixed factors and participants as random factors. Significant time by group interactions were found for the digit-span walk and subtraction walk dual-task conditions, with a reduction in DTC (gait speed) for the DTT maintained at FU. Further, absolute dual-task gait speed during walking over obstacles only improved after the DTT. Significant improvements were found for both groups in various motor and cognitive measures. However, the DTT led to better dual-task walking compared to the SMT.

Fatigability, a change in performance according to tasks and circumstances, can contribute to walking limitations in daily life. Walking-related fatigability (WF) has been assessed subjectively, but current knowledge on best objective measurement methods is limited. The aim of this study was to provide an overview of objective clinical measurement methods assessing WF in different populations. Articles were searched in Pubmed and Web Of Science by two independent raters. Studies were included when meeting inclusion criteria of measuring WF objectively in a clinical setting, with no exclusion towards any population. Case studies and reviews were not included in the review (systematic review registration number: PROSPERO - CRD42017074121). In total, 28 articles were included. The study populations were older adults (N.=7), multiple sclerosis (N.=14), spinal muscle atrophy (N.=3), osteoarthritis (N.=3), interstitial lung diseases (N.=1), and myasthenia gravis (N.=1). Data about patient characteristics, walking task, WF formula and interpretation (cut-off values and/or psychometric properties) got extracted from included literature. Every included article got checked for quality and risk of bias. WF was mostly measured during longer walking test such as six-minute walking test (6MWT) and 500 or 400-m walking test, by comparing the first and last minute or lap for spatiotemporal or kinematic changes in well-defined formulas. No gold standard is however available yet given different tasks or outcome measures across study populations. Longer walking test were most often used, with a preference towards the 6MWT, thereby comparing the changes over the last and first part of the test. Psychometric properties need more documentation before inclusion as experimental outcome.

Background: Day-to-day reliability and cut-off values to detect abnormal walking fatigability (WF) remain to be investigated in persons with multiple sclerosis (pwMS). Methods: In all, 49 pwMS (mean Expanded Disability Status Scale (EDSS) ± standard deviation (SD): 3.3 ± 1.9) and 28 matched healthy controls (HC) performed the six-minute walking test (6MWT) on two different days to determine day-to-day reliability (intraclass correlation coefficient (ICC)) and limits of agreement (LOA) for five different equations of WF. Objective: To examine day-to-day reliability, agreement and discriminative validity for measuring WF. Results and conclusion: WF expressed as the ratio between the first and sixth minute had the best day-to-day reliability (ICC’s range of 0.76–0.95 and 0.60–0.86, respectively) in both pwMS and HC, while LOA were 15% and 7%, respectively. Ecological validity and clinical importance should be further investigated.