Effects of transcranial static magnetic stimulation over the left DLPFC on gait induced fatigue in young and elderly people

Abstract

[Abstract] Gait-induced fatigue increases the risk of falls during human walking1. In this process, fatigue seems to increase the variability of gait rhythmicity, which is already higher in the elderly2. On the other hand, transcranial static magnetic stimulation (tSMS) over the left-DLPFC reduces fatigability during simple rhythmic hand movements3. Therefore, the aim of this study was to evaluate the effects of tSMS on the left-DLPFC on gait-induced fatigue in young (YH) and elderly people (EH). Twelve young (20-28 yrs-old) and 4 older (60-72 yrs-old) healthy subjects participated in two experimental sessions; all right-handed. Participants walked on a treadmill at their preferred walking speed for a maximum of two hours or until withdrawal. Fatigue was monitored every 5 minutes using a visual analogue scale (VAS). While walking, participant’s left-DLPFC was stimulated with tSMS (0.5 Tesla). In one session, tSMS was real, the was other sham. Sessions order was counterbalanced. Participants were encourage to walk for the same amount of time in both sessions. All YH completed 2h-walking in both sessions. EH walked for less time (45 min SEM 8.9) in both sessions. At the end the walk, fatigue (VAS-scores) reached 3.8 points (SEM 0.4) for Real-tSMS and 3.6 points (SEM 0.7) for Sham-tSMS in young participants (p=0.664; Student-t). In the case of the older ones, fatigue reached 4.5 (SEM 1.4) points in the Real-tSMS session and 4.9 (SEM 1.5) in the Sham-tSMS session (p=0.06 Wilcoxon). tSMS on the left-DLPFC appears to have a different effect on gait-induced fatigue in young and elderly healthy people and could prevent the development of gait fatigue in the elderly. Studies with larger samples are needed and ongoing. 1.Renner et al. Innov Aging 2020;5(1):igaa061 2.Hausdorff et al. Arch Phys Med Rehabil 1997;78(3):278-283 3.Vila-Villar et al. Psychophysiology 2022 Oct;59(10):e14078