Can we counteract muscle degeneration for long transits in space yet?

[Capt_Kirk]

@Darth_Panda

Now I’m imagining being stuck on a spaceship for 20 years which Chronos and Stranger keep trying and failing to get to spin at the correct speed, with hundreds of nauseous spacefarers being subjected to contantly varying amounts of gravity and shifts in the rate of spin…

Someone is getting pushed out of an air lock on that trip

CAPT

[Zabali_Clawbane]

@Stranger_On_A_Train

True, but then you have to have very long tethers for the spin motors, and the longer your moment arms are, the less like a rigid structure they behave, and the more non-linearities you have to cope with, especially if the structure isn’t spinning to begin with. Using a “yo-yo despin” mechanism with expendable masses is common to remove rotation on spin-stabilized systems (such as unguided sounding rockets) but you can obviously only do this once.

The point is that which spinning and despinning a spacecraft is certaining mechanically plausible and requires nothing outside of fundamental Newtonian mechanics at the college sophomore level, the actual details of implementing it on a large or inhabited apcecraft are well beyong current engineering experience and are quite complicated.

Stranger

Thank you for your replies! Good question Saint Cad, I’d like to know the answer too.

(Darth Panda, heh!)

[iamthewalrus_3]

@Zabali_Clawbane

Er, no?

You’re still misunderstanding it.

Yes, there are gravitational forces in orbit, but the the thing that causes muscle atrophy is weightlessness. Your muscles don’t have to work to move your body against gravity, and they get weaker. If you’re in free fall, you’re weightless, regardless of how close you are to a massive body.

Think of it this way: if you’re at sea level in a plunging elevator shaft (uh, in vacuum), then there are certainly gravitational forces acting on you, but you’re still effectively weightless. If the elevator shaft were deep enough to fall for 11 days, you’d experience the same muscular atrophy as astronauts do in space. The presence or absence of gravity is not the determining factor.

[Michael63129]

How do muscles weaken so fast? I’d think that the time would be much longer, say a year for that much weakening. Surely that doesn’t also mean that you lose 30% of your muscle *mass *in 11 days, especially seeing how long it can take to build it in the first place, at least if you are a bodybuilder (does this also apply if you lift weights then stop for even a week or two; the muscles now no longer do much work and would return to their normal strength/mass); if only fat loss was that easy…

[Ambivalid]

@Zabali_Clawbane

Yes, and if you had read the rest of the topic you would have seen someone else already pointed it out to me, and I admitted the mistake. Do you have anything to add, other than that?

I didn’t progress past the OP when I pointed that out. I didn’t continue on past the error before I let you know, I’m sorry that irritated you so.

[Zabali_Clawbane]

@iamthewalrus_3

You’re still misunderstanding it.

Yes, there are gravitational forces in orbit, but the the thing that causes muscle atrophy is weightlessness. Your muscles don’t have to work to move your body against gravity, and they get weaker. If you’re in free fall, you’re weightless, regardless of how close you are to a massive body.

Think of it this way: if you’re at sea level in a plunging elevator shaft (uh, in vacuum), then there are certainly gravitational forces acting on you, but you’re still effectively weightless. If the elevator shaft were deep enough to fall for 11 days, you’d experience the same muscular atrophy as astronauts do in space. The presence or absence of gravity is not the determining factor.

I do not think you got what I was saying, sez the chick in the choir…

[iamthewalrus_3]

@Zabali_Clawbane

I do not think you got what I was saying, sez the chick in the choir…

I guess I don’t. It sounded like you were disagreeing with Chronos and arguing that microgravity is substantively different than 0 gravity with respect to muscle atrophy. If that’s not what you were saying, would you explain what you were claiming?