Is it possible to prevent muscular atrophy in microgravity (space station, spacecraft etc.) by proper exercises?
Urban dwellers here on Earth can train/develop arm muscles to the equivalent of their ancestors - who used those muscles far more. It could be theoretically possible to substitute "working" with legs under Earth gravitation by intense exercises with specialized fitness equipment.
Are there any successes with preparing such set of exercises? Or, is exercise deemed trivial - do astronauts have enough time to exercise so hard while on space station?