Objectives: To clarify the cause of leg volume reduction during tiptoe movement in the standing position.
Methods: The right legs of 20 participants were assessed. The participants performed tiptoe movement in the supine position, and then stood up and performed the tiptoe movement and ankle dorsiflexion. Leg volume changes were recorded continuously using air plethysmography.
Results: Differences between leg volume changes due to tiptoe movement and the refilling volumes were not significantly different between the supine (59 mL) and standing (49 mL) positions, indicating that this amount of motion artifact was included in the downward trace recorded by tiptoe movement in the standing position.
Conclusions: Leg volume reduction during tiptoe movement in the standing position included a significant amount of motion artifacts. Therefore, it may be difficult to accurately measure the ejection volume using tiptoe movement in the standing position.
Keywords: Air plethysmography; calf muscle contraction; tiptoe movement.