Auswirkung von Schwerelosigkeit auf den menschlichen Bewegungsapparat – Erfolgreiche Maßnahmen gegen Degeneration

Langzeitaufenthalte in der Schwerelosigkeit haben die Degeneration des menschlichen Bewegungsapparats zur Folge. Verlust von Muskulatur und Verlust von Knochensubstanz sind neben der Beeinträchtigung der posturalen Kontrolle und Bewegungskoordination die zentralen Herausforderungen der humanwissenschaftlichen Weltraumforschung. Die Erfahrung vergangener bemannter Weltraummissionen zeigt: Langzeitaufenthalte im All sind für den Menschen ohne zielgerichtete Gegenmaßnahmen in Form von körperlichem Training nicht möglich. Trainingsinterventionen, die hohe mechanische Belastungen auf das muskulo-skelettale System übertragen und somit die strukturellen und funktionellen Komponenten unseres Bewegungsapparats optimal beanspruchen und erhalten könnten, stehen aktuell im Fokus des interdisziplinären Diskurses. Neueste Befunde aus Parabelflügen und Bettruhestudien haben gezeigt, dass sowohl unter künstlichen Schwerkraftbedingungen ausgeübtes reaktives Sprungkrafttraining als auch Ganzkörpervibrationstraining strukturellen und funktionellen Rückbildungen entgegenwirken können. Die Kombination beider Trainingsmethoden verspricht daher eine zukunftsweisende Lösung zum Erhalt des menschlichen Bewegungsapparats bei Langzeitmissionen im All zu sein.

During prolonged space flights, astronauts adapt to the zero gravity environment. As a consequence, they suffer from structural and functional changes. Beside the loss of bone and muscle mass, the decline of balance control and impairments in motor coordination in response to changes within the neuromuscular system are the space agencies' major concerns regarding manned inter-planetary space flights scheduled in the future. In order to maintain health and fitness during space missions, to preserve the capability to perform critical mission tasks and to counteract microgravity-induced impairments, astronauts have to perform physical exercise during spaceflight.

Space agencies and researchers currently make efforts to develop integrated countermeasures that provide high stimuli for muscle, bone and the sensorimotor system. For that purpose, bed-rest studies and parabolic flights are used to simulate a microgravity environment and to study the suitability of exercise regimens to counteract the degeneration caused by weightlessness. Two types of exercises are considered to sufficiently compensate for the lack of mechanical loading in microgravity: whole body vibration and reactive jumps performed under artificial gravity conditions. The combination of both training regimens is considered to have substantial potential to effectively counteract the microgravity-induced deconditioning of the human body.

Key words

degeneration - bone - muscle - motor control - countermeasures - whole body vibration

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