Clinical-physiological investigations for maintaining physical fitness and body composition by resistive vibration exercise

Biomedical support of astronauts will be a major element of future missions to Mars, as weightlessness causes loss of muscle and bone mass and locomotor competence if appropriate countermeasures are not effectively administered.

The aim of the proposed project is to execute countermeasures to prevent muscle and bone loss and to stimulate the cardiovascular system by continuous training. The training programme is based on the Galileo 2000-plus vibration device which is applicable in weightlessness. During the 56-day Berlin Bed Rest Study in 2003, resistive vibration exercises were introduced for the first time, and proved to be the most effective countermeasures against loss of structure and function of muscle and bone related to immobility.

The use of the Galileo 2000 system, outfitted with a vibration isolation system (a requirement during spaceflight) has already been tested during parabolic flights) though the ground-based version will be used for the Mars 500 study. A redesign of the system will incorporate sensors to monitor/measure muscle force and the effect of training.

The physical fitness of the candidates will be monitored before, during, and after the isolation period within the chamber. They will follow a defined set of test procedures at regular intervals which will monitor the development of cardiovascular and pulmonary function, muscle function, force and power as well as bone mass and strength. The candidates will exercise on the Galileo device in a standing posture and making use of springs and elastic shoulder harnesses to generate higher forces than 1g in order to make the exercise more effective.

An example of the Galileo 2000 vibration training device (Image: Novotec Medical) Even though the level of physical deconditioning will not be as great as in weightlessness, noticeable deconditioning is expected for muscle function, mental and physical health and well- being of the crew.

This protocol will make an assessment of hand grip strength as a common measure of general strength; measure force and undertake motion analysis (mechanography) using the Galileo device itself; undertake spirometry for measurement of pulmonary (lung) function; and take heart rate and blood pressure measurements as well as ECG measurements. Candidate feedback will also be used for assessment purposes.

Science Team Ulf Gast (DE) et al.