Electronic Thesis and Dissertation Repository


Master of Science




Dr. Alexandre Legros


The general public and workers can be exposed to high-levels of power-line frequency magnetic fields (MFs - up to 10 mT). Although such time-varying MFs have the potential to modulate human postural control, no existing studies have explored MF exposure levels that possibly trigger acute sway responses. This work evaluates time-varying MF exposure (up to 100 mT) in the extremely low frequency range (ELF – up to 300 Hz) and its effects on human postural control. Twenty-two healthy participants were each exposed to randomized, 5-second MF and electric stimulations (0, 50 and 100 mT and 1.5 mA respectively) given at different frequencies (20, 60, 90, 120, and 160 Hz). A force-plate collected participant Center Of Pressure (COP) displacement. Results revealed sway modulations resulting from electric stimulations but not from MF exposures. The mechanical stabilization induced by the inertia of the head-mounted exposure system might have masked acute sway responses.