Physical Countermeasure in Space: Efforts in Vain?

Abstract

This chapter gives a brief overview on the currently used physical countermeasures onboard the ISS. Based on recent skeletal muscle research data from our laboratory, we here provide a personal perspective on the still unknown answer how to prevent disused skeletal muscle fibers following gravitational unloading in microgravity from atrophy, for example, by using alternative modes of physical exercise as countermeasure in spaceflight. We still do not know why the outcome of current inflight exercise prescriptions was of little avail to the crew members, and, for example, if optimized, exercise modes targeted to cellular and molecular properties of human skeletal muscle might help to overcome disuse-induced atrophy and impaired performance control of crew members during their long spaceflight missions. Based on the exciting strengthening effects of frequency-controlled vibration mechanosignals on the key cell signaling pathways involved in the structure, function, and free radical stress management of skeletal muscle fibers and neuromuscular synaptic junctions, we propose RVE as an additional highly efficient, short duration, and compliant exercise regimen (with thousands of contraction cycles induced by neuroreflexive muscle stimulation within a few minutes of training bouts) for the safety and health of crew members in preflight training, during spaceflight missions, and during recovery on Earth.