[HN Gopher] Horizontal running inside circular walls of Moon set...
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Horizontal running inside circular walls of Moon settlements
Author : T-A
Score : 239 points
Date : 2024-05-01 23:41 UTC (23 hours ago)
(HTM) web link (royalsocietypublishing.org)
(TXT) w3m dump (royalsocietypublishing.org)
| leereeves wrote:
| Would running prevent deconditioning in muscles that aren't
| stressed by running?
| cdot2 wrote:
| Running in a circle like this would temporarily give the
| impression of higher gravity which would affect all muscles.
| leereeves wrote:
| That makes sense, thanks. So the claim here is that exposure
| to a force similar to Earth gravity for "a few laps a day"
| would prevent/reduce whole-body deconditioning?
|
| I guess that makes sense too, since a few reps of
| weightlifting every couple days is enough to trigger muscle
| growth and bone densification.
| irjustin wrote:
| In a circle, you're in an accelerating reference frame and in
| theory your body can't tell the difference.
|
| The amount of exercise you would have to do to even begin to
| remotely keep up with earth's gravity is insane.
|
| Separately, how does aging fair with zero g? can really old
| people live longer up there or is it actually worse?
| WalterBright wrote:
| Our bodies are exquisitely optimized for the surface of the
| Earth. Any deviation from that (gravity, sunlight, gas
| pressure, gas composition, radiation, etc.) is likely to be
| deleterious.
|
| This does not bode well for expanding out into the solar
| system. It might only work if we do some genetic engineering
| to make off-world habitats more habitable.
| Animats wrote:
| > It might only work if we do some genetic engineering to
| make off-world habitats more habitable.
|
| Regular engineering, of robots, will probably work first.
| Simon_ORourke wrote:
| For the life of me I can't visualize how this would with in
| practice at all.
| FriedPickles wrote:
| It would look a lot like the circular running track in SkyLab:
| https://www.youtube.com/watch?v=qiMq-fdRhLo
| leereeves wrote:
| But probably on a slight angle so the sum of the centripetal
| force and the moon's gravity is along the body axis.
|
| Or perhaps a bowl shape that you climb up the sides of as you
| speed up.
| morepork wrote:
| There are pictures in the article of their test setup with
| someone running on the wall which might help
| barbarr wrote:
| Probably something like this guy running out of a ditch:
| https://m.youtube.com/watch?v=cfXTElHLT_I
| B1FF_PSUVM wrote:
| https://www.youtube.com/watch?v=L5yislIOui8
|
| A carnival show where a motorcycle rides inside a conical well.
|
| In lunar gravity you can probably do (some of) it without the
| motorcycle.
| Nevermark wrote:
| I didn't see any mention of having a spinning surface.
|
| A tapered cylinder "gravity gym" with adjustable angled walls,
| and variable speed spinning, could smoothly create much greater
| "gravity".
|
| Spin gravity would also enable body weight exercises, core
| exercises, stationary or small area cardio like exercise bikes,
| VR games, yoga, etc. Even sleeping.
|
| _EDIT: I missed this:_
|
| > but Moon-based centrifuges allowing locomotion inside would
| pose technical challenges
|
| Still think it will be inevitable. Far more useful physically and
| psychologically. "Spinning surface" is a simple challenge,
| compared to "low-g health deterioration" and "bored to death of
| running in circles".
|
| Equipment like this might resolve issues with off-world
| childbearing. Time to "spin up" some space rabbits and see what
| we get! (Hopefully not tribbles.)
|
| Spin areas will surely become ubiquitous in all low gravity
| colonies.
|
| Startup anyone?
| fallingsquirrel wrote:
| You probably know this already, but for a while people were
| toying with the idea of a "childbirth centrifuge".
| https://patents.google.com/patent/US3216423A/en
|
| There's probably a reason it never caught on.
| Nevermark wrote:
| Reason one - We already have gravity here.
|
| Reason two - Childbirth + vertigo? WTF!
|
| Clearly they should have gone with a rudimentary linear
| accelerator such as a bungy drop or bouncing elevator type
| system!
| antonvs wrote:
| > Clearly they should have gone with a rudimentary linear
| accelerator
|
| Like a railgun.
| estebank wrote:
| While on the subject of inventions to aid with childbirth,
| I'll leave this here:
|
| https://science.howstuffworks.com/science-vs-
| myth/everyday-m...
| duskwuff wrote:
| Also the subject of an opera.
| http://www.henryakona.com/the_blonsky_device.html
| kyleyeats wrote:
| You know you have to fly all this stuff up there, right? You
| can dig out one of these pits with a shovel.
| Nevermark wrote:
| Self-sufficiency off-world is going to be much easier if
| people are healthy and happy.
|
| A "gravity gym" is going to be basic healthcare. Wherever we
| go for the long term, we will ship and/or construct them.
| maxerickson wrote:
| Yeah, that's what they said, a self sufficient way of
| constructing a gravity gym.
| usrusr wrote:
| Separate facilities for work and life, interconnected by a
| rollercoaster commute. What else has sci-fi left out?
| hedora wrote:
| I assume they'll eventually just build a big gravitron. The
| seals would be tricky (I guess the axle it spun on could
| contain a ladder and door?)
|
| Of course they could simply stop spinning it whenever they
| needed to open an airlock.
|
| (Or just put it in orbit, where these problems are easier to
| deal with and you don't need to deal with day/night radiation
| shielding/heating.)
| wongarsu wrote:
| Spin gravity in orbit has its own issues. Most notably you
| can't anchor the structure anywhere, so won't spin around the
| spin axis you want but around its center of mass. A center of
| mass that will shift as people move around, equipment is
| moved, etc.
|
| Another issue is that you need a certain scale, otherwise the
| Coriolis force as well as differential gravity (the gravity
| at your feet being higher than that at your head) lead to
| disorientation and comfort issues. The lower limit seems to
| be about 40 feet, incidentally the size of a typical graviton
| on carnival on earth. That's quite a bit wider than the
| typical rocket, and for now we are much more comfortable with
| assembling stuff in a gravity well than in orbit.
| WalterBright wrote:
| > That's quite a bit wider than the typical rocket
|
| You can have two habitats connected by a center tube, like
| an I. Rotate about the center of the I. Or a habitat and a
| cable connected to a counterweight.
|
| It's not really necessary to build a wheel.
| estebank wrote:
| In orbit, you don't even need the tube, it can be a
| single habitat with retractable cables attached to a
| counterweight of useful material that isn't immediately
| needed.
| dr_dshiv wrote:
| It could be a blown up multiwalled sphere with the heavy
| equipment in a solid cylinder in the middle. The walls
| would naturally be a bit bouncy, if under the pressure of
| the internal air.
|
| A big arena for playing professional sports could make a
| significant amount of money through televised sporting
| events.
| gmueckl wrote:
| The rotation axis could be stabilized actively by shifting
| counterweights. But the dynamics of the structure change
| depending on whether the counterweights move radially or
| tangentially. Rotation speed would fluctuate slightly in
| either case. This sounds like an interesting control
| problem!
| kevin_thibedeau wrote:
| Just put a centrifuge under a static dome. No seals needed.
| robbiep wrote:
| In the Luna series they discuss this, they basically have a
| central axis where you enter and then can 'step' up higher to
| faster spin rates/more gravity (basically a tapered cone)
| Galatians4_16 wrote:
| On the Moon, at normal pressure, humans shoud be able to get
| enough exercise in a jungle gym, or by donning a set of wings,
| flapping them to fly.
| Cthulhu_ wrote:
| Given that there is some gravity, putting on a weighted suit
| to increase their mass would also make sense, although it'd
| be unwieldy if it's not distributed exactly the same. Plus,
| getting weight into space is expensive... although probably
| not as expensive as building a wall of death or spin gravity
| structure.
| scotty79 wrote:
| Why wall of death? It's gonna be just a neat cylindrical
| room with vaguely paraboloid walls. Even if you stop
| running suddenly, dropping down from 2-3 meters in 1/6 g
| shouldn't be anything more than inconvenient.
|
| Weighted suit wouldn't help with the weight of your organs.
| They are accustomed to hanging inside you at 1g. Running on
| wall would provide them with that.
| persolb wrote:
| I was going to say "I'd be surprised if organ support is
| a large issue to an adult. We already have long term
| astronauts and people who are bed ridden for a long time
| during recovery. I would expect an issue during
| development though."
|
| Turns out there is research in this direction: https://ww
| w.ncbi.nlm.nih.gov/pmc/articles/PMC2379624/pdf/can...
|
| It seems to say that there is a long term impact on
| connective tissue hardening... but it blames lack of
| stretching; not lack of downward force. Any regular
| movement would seem to fix that.
|
| However, internally, organ tissue probably 'bounces' more
| due to gravity during movement... so less gravity means
| less flex of connective tissue.
|
| TLDR: you seem to be right
| yencabulator wrote:
| > long term astronauts and people who are bed ridden
|
| And those people lose a lot of bone mass, muscle mass,
| and need physical therapy to get back to normal function
| in 1G. Two months of bed rest will absolutely ruin you.
| There's a good reason astronauts need to be fit to begin
| with!
|
| 6 months in space causes bone loss equivalent of 20 years
| of aging. Return to Earth, do physical therapy for 1
| year, and you're still "10 years older" as far as bone
| loss goes. (https://www.sciencenews.org/article/space-
| bone-loss-density-...).
|
| Generally, as far as I know, bone growth is triggered by
| impacts (think running etc), and is hard to stimulate
| with just muscle exercises.
| scotty79 wrote:
| > Generally, as far as I know, bone growth is triggered
| by impacts (think running etc), and is hard to stimulate
| with just muscle exercises.
|
| Maybe they should do jumping while being pulled "down" by
| rubber bands.
| yencabulator wrote:
| The current microgravity solution is a treadmill for
| running that rubber bands pull you down to.
| heleninboodler wrote:
| > Why wall of death?
|
| I think that's just what the cylindrical room is often
| called when it's used for motorcycles. The paper
| repeatedly references it, abbreviated "WoD." I don't
| think there's any death involved. :)
| adrianN wrote:
| There are rocks on the moon. You don't need to bring
| weights from earth.
| TheDudeMan wrote:
| It's easier in space. I suspect it will happen there first and
| predominantly.
| jillesvangurp wrote:
| Wild idea: build one on earth to simulate 1.1G (or higher;
| whatever would still be comfortable) and put gyms, hotels,
| swimming pool, living quarters, etc. in it. Being in it for
| extended periods of time would build up muscles and bones. That
| would likely be something that fitness people and professional
| athletes would be interested in. And it's a good dry run for
| building and operating these things on Mars and the Moon. If we
| can make these things work on Earth, making them work in lower
| gravity is only going to be easier as the g-forces would be
| lower.
|
| A train or roller coaster on a slightly tilted circular track
| would probably do the job. A slight tilt would just move the
| gravity vector orthogonal to the floor.
| amstan wrote:
| Why did nobody do this yet? It would totally be a great
| prototype for stuff in orbit.
| Cthulhu_ wrote:
| Closest thing I can think of is rotating houses /
| restaurants, but they go very slowly.
|
| It would have to be big enough to avoid people getting
| dizzy, and even then it would still be a factor I think.
| That said, size/scale is less of a concern on the moon I
| would argue.
| xnorswap wrote:
| You inspired me to look up if there were many still going
| and I was saddened to discover there are no longer any
| operational ones left in the UK.
| jstanley wrote:
| All parts would be spinning at the same angular velocity,
| so unless it's really far away from its centre of rotation
| (expensive, inconvenient) you'd experience more
| acceleration near the centre than at the edges.
|
| Maybe that doesn't matter.
| scotty79 wrote:
| One of the commenters here has the right idea. Train
| riding forever on circular slanted track could easily
| house some living spaces, offices and gyms. You could
| book a stay there for few weeks and after that feel like
| you are walking on air once you come back to normal life.
| Nevermark wrote:
| Circular dome colony over a very large rotating space,
| running on concentric rings of superconducting rails.
| Spokes of slidable inner-outer weights to counter balance
| its residence's movements.
|
| Running on reliable constant nuclear power, from a safe
| distance.
|
| Maximum gravity at the tilted edges. Only natural gravity
| at the center. Enter & exit from a tunnel that connects
| under the center.
|
| Aside from the challenges of location & distance from
| Earth, if we can build small mobile cities on water (mega
| cruise lines) on the untamed ocean in Earth gravity,
| surely a small stationary spinning platter city in low
| gravity is possible.
|
| I think humans are going to find out that one g has many
| uses besides health. Good for a lot of manufacturing too.
| Gravity is a stabilizer, vertical organizer, anchor. Just
| as low gravity will have many advantages. Being able to
| quickly "adjust" gravity, by moving location, will be
| significant.
| eru wrote:
| > Being able to quickly "adjust" gravity, by moving
| location, will be significant.
|
| Who is doing the adjusting and the moving?
|
| I don't think you'd want to move anything large. You'd
| build eg your factory in the environment where it's best;
| and build a second factory in a different environment,
| instead of moving them around.
|
| However, if you eg making computer chips, you might move
| those around between different environments, depending on
| the processing step.
| Nevermark wrote:
| Yes, I meant move materials and parts between g-force
| specific equipment.
|
| If entire factories needed to "move" up and down in
| g-forces, they should be in their own variable spin
| bowls! Not sure what kind of factory that would be.
| scoopr wrote:
| I just keep thinking about this short film[0] that explores
| the views you can see with rotational artificial gravity,
| and how nauseating it could be :)
|
| [0] https://vimeo.com/869858712 also available as
| https://www.youtube.com/watch?v=iiPmgW21rwY
| actionfromafar wrote:
| https://en.wikipedia.org/wiki/Tilting_train
| eru wrote:
| You don't need to have a tilting train, you can just tilt
| the track.
| vintermann wrote:
| Spinning stuff in air takes more energy than spinning stuff
| in a vacuum.
| eru wrote:
| You would likely put these in air on the moon as well.
| Depends a bit on your design.
| jillesvangurp wrote:
| But then we do operate trains in our atmosphere so this is
| a solvable problem. The advantage outside of our atmosphere
| is of course that aerodynamics don't matter, which indeed
| would make things more energy efficient. Also there would
| be no weather (or very little of it on Mars), no humidity.
| Someone wrote:
| The acceleration needed to make a turn with radius _r_ at
| speed _v_ is. _v2 /r_
| (https://courses.lumenlearning.com/suny-
| physics/chapter/6-2-c...)
|
| If that combined that with earth's gravity has to give you
| 1.1g, that has to be (via the Pythagorean theorem) about 0.2g
| or 2m/s2. Let's pick _r = 100m_. Then, _v2_ has to be 20,
| giving as a velocity of about 16 km /hour. _r = 1km_ would
| require about 50km /hour.
|
| Sounds doable, until you consider your "put gyms, hotels,
| swimming pool, living quarters, etc. in it". That's a lot of
| mass and space.
|
| Centrifuges that we put potential astronauts and fighter
| pilots in are a lot smaller.
|
| On the other hand, there's the idea of _"a massive floating
| railway, Maglev-style, which will travel along a track with a
| radius of 2.5 kilometers within an underground vacuum tunnel.
| The machine will run on excess energy generated from wind and
| solar, and it can reach speeds up to 2,000 km /h. When the
| renewable energy production is insufficient, the kinetic
| energy from the train movement will be reconverted and sent
| to the grid."_ that engineers claim can be built
| (https://www.greenoptimistic.com/energy-train-mph/). That
| would hit over 10g and weigh a lot more than that hotel. I
| can't find updates, though.
| Someone wrote:
| Reply to self: the MVP for this probably is to walk around
| with a backpack that's 10% of your body weight.
|
| That's a lot cheaper and for many sports likely would bring
| the same benefits.
| yjftsjthsd-h wrote:
| > build one on earth to simulate 1.1G (or higher; whatever
| would still be comfortable) and put gyms, hotels, swimming
| pool, living quarters, etc. in it. Being in it for extended
| periods of time would build up muscles and bones.
|
| Is that any better than ankle weights? Or wrist, I suppose.
| hnthrowaway0328 wrote:
| Whenever I see horizontal running I thought of Sir Humphrey and
| the Christmas special.
| pmcarlton wrote:
| It takes a few clicks to get to the supplemental data movie:
|
| https://rs.figshare.com/articles/media/a_participant_running...
|
| You'd probably want to switch directions often!
| alex_young wrote:
| Why? The bungee cord is only needed for earth gravity.
| purpleidea wrote:
| Because the moon still has gravity, and there would be some
| asymmetrical force on your legs either which would be
| reversed if you went the other direction. So switch
| directions all the time to be less lopsided.
| alex_young wrote:
| The moon has a sixth of earth gravity. The force you would
| feel would be very small and the whole point of this is to
| increase the resistance against the wall you're running on.
|
| If you've ever been on a spinning wheel at a carnival where
| they move the whole thing 90 degrees it would be a bit like
| that.
|
| The track would actually be straight, so you wouldn't have
| to compensate for turning even.
|
| I'm not saying you wouldn't want to switch directions, but
| there shouldn't be some imperative to do so often.
| pmontra wrote:
| The runner will feel a pull to the left, as if the track
| had a slope in that direction. I wonder if that could give
| motion sickness to somebody. Probably people sent to the
| Moon will be selected against that because of the journey
| to and from the Moon but I really have no idea about that.
|
| Another problem, as pointed out by someone else in the
| comments, is that the floor is not flat but points upward
| and the feet and ankles might feel that. Furthermore it's
| another possible source of motion sickess (flat but not
| flat.)
| pwr22 wrote:
| It's not a symmetric exercise, look at the feet. You'd
| probably want to keep the overall workout balanced by
| alternating periodically?
| volemo wrote:
| I.e. "don't skip the left day!"
| scotty79 wrote:
| It's because walls are a bit too steep. If you made them
| into paraboloid, a per would naturally climb as high as
| they need to, to be able to run symmetrically.
| ordu wrote:
| But one leg will still be running a shorter distance then
| the other.
| croon wrote:
| This is steaming my brain a bit. Is it not the case
| (assuming an "optimal" tilt of the track) that the inner
| leg would travel more radii each step, meaning you would
| travel a larger segment of the circle on every inner step
| than outer step, ending up with an equal gait? This is my
| intuition without any formulated proof.
| scotty79 wrote:
| Person running would need to constantly turn a bit to one
| side to not climb further up the wall. So it shouldn't be
| much different from running in circles on flat surface.
|
| Not sure if runners that train by running in small
| circles are concerned about evenness and try to run the
| same amount clockwise and counter clockwise to even
| things out.
| LeifCarrotson wrote:
| Ex collegiate track and XC athlete, yes, we'd alternate
| directions once in a while when doing long workouts on
| the track. It's a 36.5m radius, and it does get to you
| eventually. You feel it in your knees long before your
| ankles. I ran distance events (1500, 3200, 5k), so I
| think I had it easier than the 200m and 400m guys (and
| especially the 400m/300m hurdle guys) whose spikes were
| desperately clawing at the track to hold the turn, but I
| did have some workouts with a lot of laps. We didn't
| bother to make it exactly even, but if we were doing
| ladder workouts we'd switch directions somewhere near the
| middle.
|
| Indoor meets often had 200m tracks with tighter
| (frequently nonstandard!) radii. The good ones were
| banked, though it never seemed to be at the right angle,
| always too steep or too shallow.
|
| Every race still goes counterclockwise, though.
|
| Maybe it's my XC side talking, but I'd love to see a
| track in a figure 8 with an underpass. Left turn, over
| the bridge, right turn , under the bridge, and repeat! It
| would break up those monotonous 8 and 12 lap races
| nicely, and you could fit a longer track in a shorter
| rectangular building by using the hypotenuse. I'm sure
| people would hate the hilly incline, though...
| iosonofuturista wrote:
| That would be extremely interesting, but the fact that
| you have an incline would change the ideal body type and
| tactics so much it would be a different sport at that
| point.
|
| But I would love to see it for medium distances, just to
| see what crazy stuff would happen!
| dmoy wrote:
| I did HS sprinting as cross training for fencing. Fencing
| is extremely asymmetric, to the point where my right
| (front) leg could lift twice the weight of my back (left)
| leg. It was freakish, and probably not healthy lol. It
| made my sprinting coach really uncomfortable, because my
| stride looked weird on the straights.
|
| The curves felt great for me though, I really liked the
| 200m better than the 100m. Can't imagine how shitty it'd
| have been for a left handed fencer to run track, because
| the big muscles would be on the inside leg.
| BLKNSLVR wrote:
| The ankle flex when the right foot lands makes me wince every
| single time. I wonder how much that's to do with the direction
| of gravity, the angle of their body looking not quite
| horizontal (and therefore 'weirding' the angle that feet hit
| the ground), and how much is to do with the individual's
| physiology.
| funnym0nk3y wrote:
| You could build it with a slight angle. Or gradually steeper
| like a high speed race track.
| nickff wrote:
| The 'bowls'/balls used for motorcycle stunt riding might be
| good examples for this (and could be fun).
| sandworm101 wrote:
| In actual lunar gravity the forces should balance out. At a
| particular speed, tied to the wall angle, the forces should
| align with the floor to let the foot land as if running on a
| horizontal surface. Imaging a motorcycle in a turn. Then tilt
| the road to match the bike's lean angle. The tire/foot then
| falls flat against the road.
| s1artibartfast wrote:
| due to the angles, it would be like running in a circle on
| earth. It is mostly a question of what the equivalent earth
| track diameter is. It can be quite painful and damaging to
| run in small circles.
| SimianLogic wrote:
| Is there a reason something like a water rower wouldn't work on
| the moon? Possibly with a weighted vest or a weighted seat.
|
| Rowing is pretty full body and doesn't seem that reliant on
| gravity.
| BenFranklin100 wrote:
| A rower wouldn't provide the same impact forces on the feet, a
| key driver of the physiological processes that maintain bone
| density in the legs, hips, and likely even spine.
| z3t4 wrote:
| Forces from the muscles are the main bone stimulator. Running
| in low gravity would probably use less muscle force then a
| rowing machine.
| infogulch wrote:
| I wonder if they use a rower on the ISS.
| safety1st wrote:
| I'm always baffled that these studies don't put more emphasis
| on resistance training, since the main issue is that your body
| no longer has to resist the forces of gravity on a day-to-day
| basis.
|
| In theory exercises like the major compound lifts should go a
| long way because they stimulate almost every muscle in the
| body. You get a lot of sustained muscle growth out of doing big
| lifts even just 2-3 times of week.
|
| Of course you're not going to be literally lifting weights in
| space because they're weightless! But resistance can be
| produced with bands, pneumatics etc.
|
| Rowing is a really good one because you get resistance training
| and cardio at the same time.
|
| But the Moon does have gravity, just less of it. Is no one
| considering just squatting and deadlifting huge-ass boulders?
| Fill a big basket with moon rocks and eventually it's gonna be
| heavy...
| knodi123 wrote:
| But you also want to have impact shocks, like your foot
| hitting the ground, to stimulate bones. Resistance training
| is certainly helpful, and perhaps a rowing machine could be
| modified to give you that shock to the legs, too.
| gadders wrote:
| Resistance training doesn't just grow muscles, it
| stimulates bone growth as well.
|
| That's why it's recommended for osteoporosis.
| maxglute wrote:
| NASA has IRED for resistence training on ISS. IIRC regiment
| was ~1xBW squats/deadlift for 3x10s in space every few days.
| Upper body was even more "normie" strength requirements. I
| think the routine included many hours of resistence training
| in general with very conservative weights to maintain mass
| and avoid injury at all costs.
| gadders wrote:
| >>~1xBW squats/deadlift for 3x10s
|
| For super-fit astronauts, that's pathetic.
| safety1st wrote:
| Dunno why this is being downvoted because it's correct.
| In their 20's most people can be at this level by their
| second session in the gym
| safety1st wrote:
| I have read about IRED but never heard the particulars of
| their training regime before. Dunno about that workout
| plan, it is a workout which would not induce hypertrophy on
| earth, so I wouldn't expect it to do much in zero g.
| Hopefully they don't give up on the idea just because they
| were doing weak lifts
|
| Really though when they get to the moon I just want to see
| them bring a barbell and two big buckets which they fill up
| with moon rocks. In general free weights are better for
| hitting a variety of muscles at once vs machines being
| better for isolation exercises, if you're trying to prevent
| muscle wastage across your entire body, a barbell may very
| well be superior!
| maxglute wrote:
| I looked list of artificial objects to lift on the moon.
|
| Lunar Roving Vehicle curb is only 76lb/34kg. That's would
| be a fun OHP set.
|
| The Descent Stage of Lunar Landing Module is 358kg/789lb.
| Probably strong man car squat with one of the legs for
| reps.
|
| Many landed probes/landers between the 1-5 plate
| territory territory.
|
| >if you're trying to prevent muscle wastage
|
| I actually like all the new light weight resistence cable
| machines that perfroms like IRED released in the last few
| years. But a 24 ft barbell with 10 ft of mooncrete bumper
| plates on each side to replicate a 5plate pull would be
| neat.
|
| I think the NASA goal is to build up muscle base on earth
| and do least impact/injury risk routine to preserve
| muscle mass and bone density. I'm assuming it's not bro
| science, and they have injury table for astronauts who
| are genpop fit but not lifter strong, and optimizing for
| that. I wonder what their policy on steriods is.
| safety1st wrote:
| Well, if nothing else there's a lot of basalt lying
| around on the moon, which would weigh about 3,000 kg/m3
| on earth. That means it should weigh around 500 kg/m3 on
| the moon. So you're gonna need some big plates, but
| getting up to the amount of weight they have people
| lifting on IRED sounds pretty doable. This way all you
| have to send over from earth is a bar and some buckets!
| eru wrote:
| > In theory exercises like the major compound lifts should go
| a long way because they stimulate almost every muscle in the
| body. You get a lot of sustained muscle growth out of doing
| big lifts even just 2-3 times of week.
|
| Keep in mind that you are doing your 3 squat sessions a week
| on top of a whole week of lugging your own body around in 1g.
| Sharlin wrote:
| Resistance training is, of course, 100% what astronauts
| already do on the ISS; how to optimally exercise in zero gee
| (and cramped conditions) has been extensively studies for
| half a century now. So it's kind of understandable if some
| one wants to study a mode of exercise that works on the Moon
| and is _not_ resistance-based.
| morepork wrote:
| They do mention that an erg doesn't have the full effect
| wanted:
|
| > Low-intensity steady-state exercise or high-intensity
| interval training on ergometers may serve to preserve
| cardiorespiratory fitness [12,25-27] but have little impact on
| muscle and bone mass.
| skykooler wrote:
| Could you do this in zero-G, too? This seems like a lot simpler
| than trying to have a section of a space station rotate and
| maintain seals around it.
| zizee wrote:
| You might like this video from Skylab:
| https://youtu.be/S_p7LiyOUx0?si=J_JqunYl2OkeROa7
|
| (23 second mark)
| peeters wrote:
| I think having some level of gravity is important for the
| simplicity of it. With a downward force it acts somewhat like a
| velodrome. You start angled upwards and as you gain centripetal
| force you gradually go more and more horizontal.
|
| Theoretically you _could_ achieve the same result in zero-g,
| but getting started is much more difficult, as are
| microadjustments in speed and balance.
| hammock wrote:
| Will we ever put men on the moon (again)? It's been 52 years
| petesergeant wrote:
| That's the plan:
| https://en.m.wikipedia.org/wiki/Artemis_program
| purpleidea wrote:
| It's very expensive. The plan needs serious improving.
| Cthulhu_ wrote:
| Looks cheaper than the Apollo program when adjusted for
| inflation (Apollo was $257 billion in 2023 dollars)
| eru wrote:
| If you want to make it look even cheaper, you can adjust
| for GDP growth instead.
|
| (It's still very expensive in absolute terms, and you can
| have a discussion about whether it's really the best use
| of tax payer funds.)
| rokkitmensch wrote:
| Skateboarding on the moon is going to /killllll/.
| morebortplates wrote:
| Swimming would be a pretty interesting experience as well. You
| probably could even walk on water.
|
| https://what-if.xkcd.com/124/
| abecedarius wrote:
| https://en.wikipedia.org/wiki/The_Menace_from_Earth
|
| I'm not sure how realistic the muscle-powered flight is, but
| a different form has been done on Earth.
| romanhn wrote:
| Reminded me of circular wall running in 2001 Space Odyssey more
| than 50 years ago: https://youtu.be/1wJQ5UrAsIY
| OscarCunningham wrote:
| If he ran in the same direction as the station was rotating
| then he would feel extra force pushing him into the ground,
| whereas running the other way would cancel some of the
| centrifugal force. I wonder if the directions would feel like
| 'uphill' and 'downhill'. I assume for training purposes you
| would probably want uphill. I don't know if the movie gives you
| enough information to work out which way the spinning section
| is going.
| corlinp wrote:
| Finally I get to be that guy in the comments with a weird about
| of relevant experience. I built the world's largest hamster wheel
| in 2012[1], a large rotating circular platform ~6m in diameter.
|
| It was a fun and unique experience to run on for a short amount
| of time, but most people would get dizzy after a few minutes of
| jogging on it. The curved platform also turned out to be a bit of
| a tripping hazard. It was more often used as a sort of swing
| (could this work on the moon?).
|
| I'm skeptical that the experience on the moon will be much
| better, especially since the diameter they're proposing is even
| smaller.
|
| 1. https://sdusd-newsfeed.blogspot.com/2012/09/pt-loma-high-
| sen...
| antonvs wrote:
| With a hamster wheel, aren't you basically running in one spot
| near the bottom? If so, do you know what causes the dizziness?
| corlinp wrote:
| Because you're looking forward at the platform that's moving
| down and toward you. Kind of like if you were to stare down
| at the belt of a treadmill while it's moving - it would be
| disorienting after a while.
| avar wrote:
| Doesn't this boil down to a claim that blind people are
| incapable of running on a constant upwards slope due to
| motion sickness?
|
| Because even if your claim is correct, and the conflicting
| visual input is disorienting, the Moon-dweller on a similar
| contraception could just close their eyes.
| bloppe wrote:
| Staring down is not equivalent to being blind. Motion
| sickness occurs when signals from your eyes (like the
| motion of the world around you), body (like wind on your
| face) and auricular semicircular canals (organs in your
| ear that sense acceleration) conflict with one another.
| In theory, your brain reacts to this with nausea because
| historically that situation would mainly arise due to
| illness or poisoning, so it might be good to vomit.
| That's why you can sometimes alleviate car sickness by
| opening a window (convincing your brain that you're
| definitely moving) or, if you're driving at constant
| speed, refraining from looking out the window (convincing
| your brain that you're stationary).
|
| Blind people only have 2 out of the three signals so they
| might be less prone to motion sickness.
| terribleperson wrote:
| If this dizziness is anything like VR sickness, you can become
| acclimated to it.
| eru wrote:
| And you might actually just wear VR (or augmented reality,
| AR) goggles to counteract it.
| DemocracyFTW2 wrote:
| Running around in circles sounds like a great way to fight
| boredom. Right next to their aptly named Wheel-of-Death device
| there's an entire room dedicated to paintwatching, which is a bit
| like birdwatching, or at least so says the promotional material.
| pugworthy wrote:
| Shades of 2001: A Space Odyssey
| latchkey wrote:
| I spent so many years riding bikes in circles on a velodrome.
| Doesn't seem too different.
|
| When I would ride behind a motorbike, at 40+ mph, it was effort
| to just keep my body from being pushed down into the handlebars.
| At 50+, my tires would start to skip upwards/outwards.
| TaylorAlexander wrote:
| Velodromes already seem cool to me, so a velodrome on the moon
| seems cool as hell.
| semi-extrinsic wrote:
| Keep in mind if you are putting in enough speed to get
| rotational acceleration of 0.5 G on Earth, that would be around
| 1.3 - 1.4 G total acceleration (depending on the bank angle).
| But on the moon it would just be 0.5 - 0.6 G.
| latchkey wrote:
| Very interesting point, thanks!
| slyall wrote:
| The book "Imperial Earth" by Arthur Clark featured a circular
| cycle track on a low-gravity spaceship.
|
| The main protagonist was trying to train for earth gravity so he
| cycled around it very fast until he felt 1G
| martyvis wrote:
| There was a zero G running track in the movie "2001: A Space
| Odyssey"
| n1b0m wrote:
| Is this the same concept as the running scene in the film 2001: A
| Space Odyssey?
| jiri wrote:
| Actually no. In the movie, there is already gravity present in
| the hub - generated by rotating this large cylindrical hub.
| Running in such hub would increase gravity slightly but no
| running is needed at all! Just being in such hub is comparable
| to running in cylinder mentioned in the paper.
|
| Running in small (10m) diameter cylinder increase gravity
| significantly without need to spin the cylinder.
|
| Anyway to minimize effects of Coriolis force in spinning
| cylinder, I think that the size of the cylinder would be
| significantly larger than the size in the movie.
| abecedarius wrote:
| Are you thinking of the space station? The running scene was
| in the interplanetary ship, with a 12m diameter cylinder
| spinning just enough for moon-level gravity.
| https://en.wikipedia.org/wiki/Discovery_One
| gadders wrote:
| >>Long-lasting exposure to low gravity, such as in lunar
| settlements planned by the ongoing Artemis Program, elicits
| muscle hypotrophy, bone demineralization, cardio-respiratory and
| neuro-control deconditioning, against which optimal
| countermeasures are still to be designed. Rather than training
| selected muscle groups only, 'whole-body' activities such as
| locomotion seem better candidates,
|
| I don't get why whole body locomotion would be the best way to
| combat muscle hypotrophy and bone demineralisation when that is
| not the best method on earth.
|
| A better approach would be using bands or even moon rocks to lift
| weights etc.
|
| Just set new lunar records for the deadlift, squat etc.
| eru wrote:
| > I don't get why whole body locomotion would be the best way
| to combat muscle hypotrophy and bone demineralisation when that
| is not the best method on earth.
|
| Whole body locomotion is approximately the only way we have
| ever tried on earth to combat muscle hypotrophy. So we don't
| know whether that's the best method or not: we just haven't
| tried anything else.
|
| To be more precise, any method we have tried on earth, be that
| bands or weight lifting etc _also_ included a hefty dose of
| whole body locomotion inside a strong gravity field.
|
| (You can get great results from hitting the gym for squats and
| deadlifts three times a week for an hour. But that regime also
| includes 24/7 exposure to 1g of gravity.)
| gadders wrote:
| Got you. So we would need to do the experiment to try
| resistance training in low/no gravity to see whether it would
| work or not.
|
| It would seem like the obvious thing to try though as it is
| the best method in regular gravity.
| eru wrote:
| Oh, it's definitely something we should try. We need a lot
| more experiments.
|
| The only thing we know for sure is that moving around in 1g
| is generally enough for our bodies. Especially once you
| throw in a bit of deliberate exercise. We also already know
| from our space stations that 0g is bad for you, and even
| exercise can only mitigate some of the damage.
|
| But that's already the limit of our definite knowledge.
|
| But we don't know where the boundaries are, and whether the
| transition is smooth. Eg I would suspect 0.01g to be still
| pretty bad, and 0.99g to be indistinguishable from earth
| for our bodies. But would 0.9g be enough? Probably yes, but
| who knows? What about 0.5g? Is it bad? Is it 50% as bad as
| 0g?
|
| Would 0.2g give you 80% of the benefits of 1g? We don't
| know.
| cnity wrote:
| Possibly dumb question, but if you wore weighted vests
| (for example) to match the same force due to gravity on
| earth for that individual, would that be equivalent to
| existing on earth without the vest? Ignoring e.g. the
| difference in exact distribution of the weight.
| eru wrote:
| There are some differences, eg how your organs sit inside
| your body.
|
| Perhaps your liver works best in 1g? We can make some
| educated guesses, but honestly we don't know! No one has
| run experiments.
| netman21 wrote:
| Now I envision a multi-story lunar habitat with a 30 foot
| diameter well that you have to run on to get from one level to
| the next. At least to get up. Getting down may just involve
| jumping down.
| Nevermark wrote:
| > Moon-based centrifuges allowing locomotion inside would pose
| technical challenges and demand substantial electrical energy.
|
| Comments:
|
| > would pose technical challenges
|
| That's a very funny disadvantage to call out! "Technical
| challenges" are how you know you are on the moon.
|
| A stable rotating system would seem to be one of the simplest
| possible lunar challenges. If it is implemented within an
| existing environment shell, it could be quite low tech.
|
| > demand substantial electrical energy.
|
| Maintaining rotation in low Earth gravity should be a very low
| energy process. The only energy loss would be friction at the
| point of rotation, which should be minimal, and some position
| controlled weights, for maintaining balancing in the context of
| human movement.
|
| But the proposed no-tech solution has a great return on
| investment, and is realistic for early days, or infrequently
| inhabited outposts.
| nicklecompte wrote:
| One question I have that I didn't see addressed in the article:
| how does the inner ear work in low gravity? I wonder if this
| might make astronauts unusually dizzy on the moon because of
| differences in the vestibular system.
|
| This article seems like a good survey of the general impact low-g
| has on the inner ear changes, but I've barely skimmed it:
| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8595211/
| delecti wrote:
| There have been studies on the subject, and participants could
| adapt to rotations as high as 23 RPM. In this test they were
| more in the 5-10 RPM range (depending on which iteration and
| how fast the participants were running), so it'd probably be
| fine after some adjustment.
|
| https://pubmed.ncbi.nlm.nih.gov/14703662/
| nicklecompte wrote:
| That is interesting, but my concern is a bit different than
| that article - I'm worried about what happens when the
| astronaut stops. After they are done running, they will be at
| rest in a low-g environment (unlike this experiment), but
| their inner ear fluid will have most of the momentum it had
| while they were running - this is the physiological basis of
| merry-go-round dizziness.
|
| On earth the fluids quickly settle and the dizziness fades. I
| wonder if maybe it would take considerably longer on the
| moon. It is probably something they can adjust to, but I was
| wondering.
| delecti wrote:
| I doubt they'd just _stop_. I imagine in practice this
| would be more of a parabolic track, and they 'd slow to a
| jog after the peak of their workflow. That would give time
| for their cochlear fluid to slow down as well.
|
| And even that aside, I'm not sure the lack of gravity would
| change how quickly cochlear fluid settles. I think that
| settling is due to resistance from the fluid turbulence of
| the cochlear canals, not due to gravity.
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