Measuring walking-related performance fatigability in clinical practice: a systematic review

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.