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Updated: Aug 26, 2026

Single Fiber Isolation Assay for the Assessment of Oxidative Myofiber Behavior
Published on: March 31, 2026
Structural and metabolic characteristics of human soleus fibers after long duration spaceflight
I N Belozerova1, T L Nemirovskaya, B S Shenkman
1SRC Institute for Biomedical Problems, RAS, Laboratory of Myology, Moscow, Russia.
Abstract:
The fiber size decline, alterations in fiber metabolic potential and increase of connective tissue component were shown in human m. vastus lateralis after short and long-duration space flights and in m.soleus and m.vastus lateralis after 120 day head down tilt bed rest. It is known from rat and monkey studies that the exposure to weightlessness leads to the most pronounced changes in postural muscles, e.g. m.soleus. It was shown that 17 day space flight induced significant decrease of fiber cross-sectional area and slow-to-fast fiber type transformation in human soleus. But in the cited work the fiber population under study was limited like in most single fiber technique analyses. The present study was purposed to investigate the structural and metabolic properties of soleus muscle in Russian cosmonauts exposed to 129-day space flight on board of the International Space Station.
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