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Microgravity-induced muscle atrophy: Implications for long-duration spaceflights
- temptemptemp111 3y ago[dead]
- 3seashells 3y agoCould Ems or sleeping in a spinning drum overcome this?
- inamberclad 3y agoEMS = electro muscular stimulation? No, not 100%. Astronauts have very good resistance training onboard the ISS at this point. Some of them come back to earth stronger than they left. However, it turns out that your body also needs skeletal loading in order to produce strong bones. That kind of loading comes from having large forces distributed through the entire body. NASA tried a variety of shortcuts around resistance training, but none of them were satisfactory. A spinning drum is probably the best method short of artificial gravity, but it has a couple problems. A rotating reference frame creates some pretty non-intuitive effects (https://www.youtube.com/watch?v=bJ_seXo-Enc https://www.youtube.com/watch?v=bJ_seXo-Enc). Research is ongoing about just how fast a human can be spun for a long duration, although data is hard to come by. We also don't know how low of a gravity a human can stay healthy in without intervention like serious exercise. If it turns out that you need 1G, that involves a much larger spinning drum than a G/3 (Mars) or G/6 (Moon) environment. The problem is that we really have no way to simulate those environments for a human.
- mealkh 3y agoWhat about flywheel training? You can do deadlifts, squats etc with it that will produce large spinal/skeletal load even in the absence of planetary gravity due to the inertia. Something like https://exerflysport.com/ https://exerflysport.com/ or https://exxentric.com/store/kbox/ https://exxentric.com/store/kbox/
- RetroTechie 3y agoGiven the travel time, any visit to Mars would probably not be short-stay like 1 day. More likely weeks, months or longer. So you'd have Mars G for time on the surface anyway. And besides: a few astronauts have already done long duration microgravity, returned to Earth & lived to tell.
- inamberclad 3y agoSure, but NASA is concerned about an emergency landing scenario on Mars. Astronauts that crash land while physically incapacitated from long duration microgravity will face near certain death.
- MilStdJunkie 3y agoOne of the saddest parts of the science fiction novel _Aurora_ is that natural born human populations will have serious problems permanently separated from the larger ecosystem they're evolved for. It's a valid hypothesis. Humanity would need to have an entire engineered biosphere to replace the biome living in our guts, our eyes, our . . everywhere. And anywhere we find that's close enough to Earth to live in, will have . . something else . . almost certainly[1] already there. Kim Stanley Robinson isn't an easy read if you're on the other side of the political spectrum, but Aurora is comparatively free of his standard preachiness, at least in my ears. I actually disagree with his primary thesis of Aurora, and the novel suffers from some fundamental problems as a story, but the point is still salient. Humans will have to build their own Earth, wherever they end up, either out there or back here. I have a funny feeling we won't learn to treasure our own planet until we find out how much work it is to live on another. [1] Particularly given the extraordinarily early date of the first Terran lifeforms. It doesn't seem to take too much to get the ball rolling, unless the panspermia theories actually turn out to hold some water.
- diogenes4 3y ago> I have a funny feeling we won't learn to treasure our own planet until we find out how much work it is to live on another. Optimistic! I have a feeling we won't learn to treasure our own planet until we fail to reach another. The problems here are simply too massive for us to coordinate spreading to other places.
- shiroiuma 3y agoWe'll learn to treasure our own planet when the ecosystem becomes uninhabitable for us and we start going extinct.
- kzrdude 3y ago"Earth is our spaceship"
- shiroiuma 3y ago>And anywhere we find that's close enough to Earth to live in, will have . . something else . . almost certainly[1] already there. *No* place is going to be "close enough" to Earth to live in: the closest star system is 4 light-years away, and will take tens of thousands of years to travel to with anything remotely like current technology. The only way we're going to find another planet "close enough to Earth to live in" is if we invent a real, working, practical FTL drive. That's not terribly likely. Well, there is one other possibility: some glowing blue alien substance called "protomolecule" is discovered in our solar system and somehow (through a long, twisting plot arc) takes over an asteroid with 100k people, assimilates their biological matter, crashes on Venus, then travels to the outer system and builds a Ring Gate. Anyway... Basically, we're stuck with this planet, the not-at-all-like-Earth worlds near it, and the other resources of this system. The only real way we're going to create a viable, Earth-like colony is to build an O'Neal Cylinder.
- suzzer99 3y agoThis seems like a real problem for older astronauts who will never be able to gain that muscle back. Muscle mass is so vital for long term health. 70-year-olds confined to bed rest for just two weeks have been observed to lose significant muscle mass that they most likely will never get back. Obviously most astronauts are younger than 70. But they're also losing a lot more muscle mass and bone density.
- inglor_cz 3y agoProgress in stem cell treatments might be able to treat that muscle mass loss. We are getting closer to regenerating tissues at will, although obviously the main effort is concentrated on the cardiovascular system and nerves.
- voldacar 3y agoYou could just give the 70 year olds testosterone replacement and they would gain it back and more, probably
- dmarchand90 3y agoI wonder if you could bypass these issues with strength training machines designed for space. E.g a squat machine that pushes down from above, cable tension based arm movements, etc. I bet if you're clever you can probably have a small room that can get the essential exercises in and takes up a similar amount of room as a toilet
- HPsquared 3y agoThe ISS has a space barbell: https://en.wikipedia.org/wiki/Advanced_Resistive_Exercise_Device https://en.wikipedia.org/wiki/Advanced_Resistive_Exercise_De...
- dmarchand90 3y agoNow I'm curious how the results of study posted would be mitigated by the space barbell
- HPsquared 3y agoI guess the problem remains that the legs still don't need to lift the body weight. For example in a barbell squat, your shoulders lift the bar, but your legs lift that weight plus your bodyweight. In space, bodyweight is not a factor so your legs only have the same load as the shoulders. So upper body / shoulder might end up being the limiting factor, not giving the legs the same amount of load they would under gravity.
- vmfunction 3y agoYou can always just train like some anime character or kung fu masters: https://www.youtube.com/watch?v=crKohKpVoAM https://www.youtube.com/watch?v=crKohKpVoAM
- freilanzer 3y agoThat could be solved via a vest that you wear, that has additional cables pulling with a force of the bodyweight. That way you could also do pull ups with your bodyweight.
- amelius 3y agoHere's my design for solving this problem. Instead of sending one rocket, you send two. You link them with steel cables. Then you rotate them around to generate the required gravity.
- stoneman24 3y agoYep, see Netflix film Stowaway for example. Once we get Spacex Starship working, fit 2 of them with Hab modules in the nose. Launch them and connect together at the nose and spin at different rates for moon gravity (G/6) and Mars gravity G/3). Use steel cables to increase radius and reduce required spin rate. A relatively cheap (for space) setup to get some good actual measurements.
- uoaei 3y agoThe whole "space is big" thing applies here, you can keep those two bodies super far apart. I don't really see a good reason for that tbh but it's possible. Though if the mission depends on those two bodies traveling together, you better have tons of redundancy or some propulsion systems to recover in case the cable snaps.
- stoneman24 3y agoWas really thinking of an earth orbiting laboratory setup with a radius of about 250m and rotation speeds of about 2-3 rpm. Need to model it when I have some time. Just to gain actual data on different gravities and durations. The starship has plenty of room for the habs to run experiments on plants and people. Each one has propulsion in case of a cable failure. You’re correct, the cable snapping would be big concern.
- yencabulator 3y ago> Though if the mission depends on those two bodies traveling together Nevermind together, if the cable snaps they won't be going to the original destination.
- bjelkeman-again 3y ago
- Brometheus 3y agoDon't live in microgravity.
- iampivot 3y agoI wonder if it's really required to have 1g gravity in order to avoid this. It's much easier to artificially create, say 1/6g (moon) gravity by rotation than 1g, since rotational speed required is quite a bit slower.
- uoaei 3y agoI wonder how much the rotation speed really matters. It comes down to the tensile strength of the material required to hold everything together I suppose but most metals should be able to handle 1g just fine. Once it's rotating you don't need much energy to keep it going, just enough to overcome any frictional losses from whatever interfaces happen to be required.
- iampivot 3y agoThere's also the issue of dizziness if rotating fast with a small radius.
- leoff 3y agoCould one become stronger by living in 2g?
- heavenlyblue 3y agowould that be similar to weari nb a backpack having weight same to your body?
- reportgunner 3y agoNot too similar, imagine all the liquids in your body while running at 2g.
- stoneman24 3y agoTo echo some of the points from the aurora book, I think that the human body is really well optimised for 1G environments. We know that there are issues in zero gravity. As you adapt to 2G, you may well get stronger but the stress and strains may have a severe effect on health, life expectancy. Hate to think about the effects on your blood pressure etc Your great grand kids might eventually cope.
- deleted 3y ago[deleted]