Changes in Posture Following a Single Session of Long-Duration Water Immersion

• Published in: Journal of applied biomechanics 2018-12, Vol.34 (6), p.1-441
• Main Authors: Glass, Stephen M, Rhea, Christopher K, Wittstein, Matthew W, Ross, Scott E, Florian, John P, Haran, F Jay
• Format: Article
• Language: English
• Subjects: Diving; Posture; Water
• ISSN: 1065-8483; 1543-2688
• DOI: 10.1123/jab.2017-0181

Transitioning between different sensory environments is known to affect sensorimotor function and postural control. Water immersion presents a novel environmental stimulus common to many professional and recreational pursuits, but is not well-studied with regard to its sensorimotor effects upon transitioning back to land. We investigated the effects of long-duration water immersion on terrestrial postural control outcomes in veteran divers. Eleven healthy men completed a 6-hour thermoneutral pool dive (4.57 m) breathing diver air. Center of pressure was observed before and 15 min after the dive under four conditions: 1) Eyes Open/Stable Surface (Open-Stable), 2) Eyes Open/Foam Surface (Open-Foam), 3) Eyes Closed/Stable Surface (Closed-Stable), and 4) Eyes Closed/Foam Surface (Closed-Foam). Post-dive decreases in postural sway were observed in all testing conditions except for Open-Stable. The specific pattern of center of pressure changes in the post-dive window are consistent with 1) a stiffening/overregulation of the ankle strategy during Open-Foam, Closed-Stable, and Closed-Foam, or 2) acute up-weighting of vestibular input along with down-weighting of somatosensory, proprioceptive, and visual inputs. Thus, our findings suggest that post-immersion decreases in postural sway may have been driven by changes in weighting of sensory inputs and associated changes in balance strategy following adaptation to the aquatic environment.