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Horizontal running inside circular walls of Moon settlements

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Re: Horizontal running inside circular walls of Moon settlements

#131

Post by alex_young »

purpleidea wrote: post #68
alex_young wrote: post #49

Earlier quoted context omitted.

Why? The bungee cord is only needed for earth gravity.

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.

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.

Re: Horizontal running inside circular walls of Moon settlements

#132

Post by nickff »

funnym0nk3y wrote: post #84
BLKNSLVR wrote: post #81

Earlier quoted context omitted.

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.

You could build it with a slight angle. Or gradually steeper like a high speed race track.

The ‘bowls’/balls used for motorcycle stunt riding might be good examples for this (and could be fun).

Re: Horizontal running inside circular walls of Moon settlements

#133

Post by pmontra »

purpleidea wrote: post #68
alex_young wrote: post #49

Earlier quoted context omitted.

Why? The bungee cord is only needed for earth gravity.

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.

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.)

Re: Horizontal running inside circular walls of Moon settlements

#134

Post by delecti »

nicklecompte wrote: post #128

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/

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/

Re: Horizontal running inside circular walls of Moon settlements

#135

Post by nicklecompte »

delecti wrote: post #134
nicklecompte wrote: post #128

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/

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/

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.

Re: Horizontal running inside circular walls of Moon settlements

#136

Post by Someone »

Someone wrote: post #117
jillesvangurp wrote: post #73

Earlier quoted context omitted.

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 Mo…

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 y…

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.

Re: Horizontal running inside circular walls of Moon settlements

#137

Post by safety1st »

maxglute wrote: post #126
safety1st wrote: post #123

Earlier quoted context omitted.

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 fi…

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 ca…

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!

Re: Horizontal running inside circular walls of Moon settlements

#138

Post by delecti »

nicklecompte wrote: post #135
delecti wrote: post #134

Earlier quoted context omitted.

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/

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…

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.

Re: Horizontal running inside circular walls of Moon settlements

#139

Post by dmoy »

LeifCarrotson wrote: post #124
scotty79 wrote: post #115

Earlier quoted context omitted.

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.

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…

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.

Re: Horizontal running inside circular walls of Moon settlements

#140

Post by yjftsjthsd-h »

jillesvangurp wrote: post #73
Nevermark wrote: post #12

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 locomotio…

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 Mo…

> 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.

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