Effect of prolonged sitting immobility on shear wave velocity of the lower leg muscles in healthy adults: A proof-of-concept study.

Abstract

ObjectiveThe purpose of this study is to investigate the physical changes of the lower leg muscles in the compartment by observing the changes in the shear wave velocity of the gastrocnemius, soleus and tibialis anterior muscles with time in the sitting position for 2 hours and after elevation of the lower leg.Materials and methodsThe subjects were 24 healthy adult males (average age 26.6 years). Shear wave velocity was measured by Aplio 500 in immobilized leg immediately after the start of sitting, 60 minutes and 120 minutes after the start of sitting. After 120 minutes the subjects raised the lower leg for 3 minutes, then measured again.ResultsIn the lateral and medial gastrocnemius, there was a significant increase in the velocity at 60 (1.58 ± 0.06, 1.70 ± 0.09 m/s) and 120 minutes (1.70 ± 0.10, 1.83 ± 0.11 m/s) after the start of the test (1.52 ± 0.06, 1.66 ± 0.10 m/s), respectively (pConclusionsIt has been reported that the change of shear wave velocity with time is proportional to the intramuscular pressure in the leg compartment, and it is assumed that the increase of shear wave velocity in the 2-hour seated leg is due to fluid retention in extra-cellular space of the compartment.