Gathering your 'sea legs': Extended durations in an offshore environment increases postural sway excursions.

Abstract Background Mal de debarquement (MdD), or often called ‘sea legs’, is the perception of self-motion after exposure to passive movement such as being on a boat at sea. Previous studies highlight sensory re-organization difficulties and postural control impairments after disembarking from sea travel in experienced crew members. However, the impact of MdD in individuals with has not been investigated. Research Question Does prolonged exposure to boat motion while at sea impair static postural control after disembarking in individuals with minimal offshore experience? Methods Healthy adults (n = 24) with minimal offshore experience had their static balance assessed on a force platform before (PRE) and after (POST) a 7 -h deep sea fishing excursion. Static balance was tested in eyes open (EO), eyes closed (EC), eyes open on a foam surface (FEO), and eyes closed on a foam surface (FEC) conditions. Sway excursion, sway velocity and sway variability in the medial-lateral (ML) and anterior-posterior (AP) directions were computed and then compared PRE/POST using a paired t-test (p  Results Significant increases in ML sway excursion (p = 0.004), ML sway range (p   0.05). Significance Increases in postural sway excursion and variability were observed in individuals with minimal offshore experience after disembarking. Our findings suggest sensory re-organization difficulties in order to maintain an upright posture in challenging sensory conditions dependent on vestibular and somatosensory inputs following exposure to boat motion at sea.